(FORTUNE Magazine) – I remember seeing Greg when all was crazy with the world. It was February of last year, and he was about to appear on CNN to talk about his company, Mediaplex. When I met him in the little off-camera waiting area, I barely recognized him. He was wearing some fine Italian suit. He was surrounded by PR people and assistants. And there was a buzz around him. He seemed to have developed this...presence. Suddenly I realized what Greg--that is Greg Raifman, my old school pal from the track team--had become. There, standing in front of me, was that uniquely turn-of-the-century species: an Internet billionaire CEO! Just like what you read about! (Or in my case, wrote about.) I was just about to say something to that effect when a young CNN production assistant slipped up to us and pulled Greg away. "Mr. Raifman," she said, "it's your time."

In a sense I guess all of us know Greg. If we didn't take part directly in the Internet gold rush, we know somebody who did--the friend who left a secure job for a dot-com, the relative who rode Net stocks up and forgot to sell on the way down. But Greg's experiences went way beyond any of that. Greg was in the outer limits. He's a guy who created a company worth $4.5 billion at one point. A guy whose net worth peaked at over a billion dollars. And now, poof! Eighteen months later that great wealth is almost entirely gone. We're not talking about a dot-bomb celebrity like Jeff Bezos or Jay Walker. We're talking about a guy I used to drink Bud talls with.

Greg and I first got to know each other some 25 years ago at Bethesda-Chevy Chase High School in the Maryland suburbs of Washington, D.C. We weren't best buddies or anything, but we were friendly, and I knew him pretty well. Over the years we stayed in loose contact, though by the 1990s we didn't communicate much. Then, when Greg made it big as an Internet CEO, we became reacquainted, which wasn't surprising: He was running a hot technology company, and I was writing for a high-profile business magazine. But by last fall, with the market and Mediaplex's stock tanking, we spoke less frequently. Greg drifted back out of my life.

And then one day this spring, a year after the deluge, I happened to check on Mediaplex's stock. Whoa! MPLX had tumbled from $104 all the way down to under $1. Questions flooded my mind: What happened? Was Greg okay? Was he broke? And then more questions: How is it that some guy from high school makes a billion dollars? (Or, where did I go wrong?) Was Greg someone special, or did he just stumble into a once-in-a-century hot zone? And what did it feel like to lose so much dadgum money? I decided to find out what had happened to my friend during that supernova flash of irrational exuberance.

Washington, D.C., used to be known as a sleepy Southern town masquerading as a big city, and even in the late 1970s that was true to an extent. Greater Washington's boom was still a half-decade off (that came when they put in the Metro), and nothing much had been built in Bethesda in 15 years. There was still a bluegrass bar and a crab shack in town. As for our school, B-CC, as it's called, was a mix. Once one of the finest public schools in the country, it had become threadbare over the years, though it still sent dozens of seniors to the most selective colleges. Along with the upper crusties from Chevy Chase were a few poor Hispanic kids and some black kids from Silver Spring.

There weren't many signs about Greg back in high school that pointed toward his becoming a billionaire, but there were a few. Greg and his two older brothers, Larry and Alan, grew up comfortably middle class in a split-level brick house in North Chevy Chase, one of that town's more modest neighborhoods. His father, Irving, a clinical psychologist, was something of an entrepreneur: He built a successful company called Consultation & Guidance Center. "Paid for the boys' college," Irv told me recently. Greg's mother, Grace, who later loved nothing better than to talk tech stocks with Greg, was a teacher and an administrator with a Ph.D. in educational psychology.

I don't remember meeting Greg for the first time. The track season began and he was just there, a tall, gangly, kind of goofy dude. (I guess we were all kind of goofy back then, right?) He was a friendly guy, not particularly loud, with an open personality. Greg's moods would swing from good-natured ribbing to reflective seriousness.

B-CC had a rich tradition of outstanding track and cross-country teams and athletes, but neither Greg nor I did much to uphold it. He was an okay high hurdler, and I was a pretty average distance runner. In our high school yearbook the caption next to the winter track picture reads: "Greg Raifman surprised some seasoned competitors in making sixth in the 60-yard hurdles." Later I would tease Greg that I was sure there were only five high schools in Montgomery County. On the other hand, Greg's best friend, Reggie Sanders, was the real deal. All-state cross-country runner and miler. A starter on the basketball team. Reggie, who went on to UVA and Yale medical school and is now an eye surgeon affiliated with Georgetown University Medical Center, was in another league as far as sports went. (Greg remembers the three of us running on the same mile-relay team and winning a race. If so, you best believe most of that had to do with Reggie's anchor leg.) In any event we all had a great time on that team, though to this day I can't understand why both Reggie and Greg called me "Scruffy."

I called Reggie recently and spoke with him for the first time in 24 years. He knew all about Greg and had already reflected on his journey. "Greg was driven, but he was always searching too," he said. "You and I kind of had our thing in high school, and we both went out focused into the world. Greg checked out this group of people, he tried that, he was always looking." I'd never thought about that. Did Greg's restlessness (or was it insecurity?) serve as a kind of emotional propeller? Do all entrepreneurs have that? Was I really doing stuff in high school that pointed me down my road? (Gee. I guess so. I was an editor at the school newspaper.)

When Greg turned 18, his dad Irv told him: "Here's a bank account with $20,000 in it. That's your money for college." The University of Michigan, which Greg attended, charged about $6,000 a year tuition, so he was a little short. "I think by giving me the money up-front, my dad was trying to give me some responsibility," says Greg. "I had to invest it and work summers to make up the difference."

At Michigan, Greg dated Carla Feldman, a gal from our high school who went on to become an executive at Hewlett-Packard. And he majored in economics. "Greg also bought a dog," his father recalls with a laugh. "It was a malamute, and he named him Keynes." (Better than Schumpeter, I suppose.)

Greg went on to Georgetown Law school, where he met his future business partner, Jon Logan Edwards. A smooth-talking litigator and the son of the basketball coach at the University of California at Berkeley, Edwards came to G-town by way of Dartmouth, where he was captain of the basketball team. "Yes, Greg and I are different," Edwards says. "He's a Jew; I'm Christian. He's tall; I'm short. I'm an athlete; he's not." But as so often happens with odd couples, the two hit it off. On the basketball court, at law review, and at bull sessions, Greg and Edwards talked of practicing law together.

First, though, they would go in opposite directions. Edwards returned home to the Bay Area, taking a job with the law firm Brobeck Phleger. Greg went to southern Georgia to clerk for U.S. District Judge Anthony Alaimo. "I really thought Greg was settling in," recalls Reggie Sanders. "He was dating some pretty gals, and he had a motorcycle. But more than that the judge liked him, and Greg seemed to really love the law."

After his clerkship, Greg moved to L.A. and joined Latham & Watkins. But instead of setting his sights on a partnership at the blue-chip firm, Greg began a job journey that drew him into dealmaking.

Greg and Jon Edwards stayed in touch, though their relationship had developed a competitive streak. "We were playing hoop back then in L.A. in a lawyers league, and I broke my ankle in the first half," recalls Greg. "Jon said to me, 'Suck it up, tape an aspirin to it, and get back in the game.' " Jon chuckles at that one: "It wasn't really broken." Greg: "Right. I'm the one with my foot in a cast for a month." (Felix! Oscar! Please!)

In 1985, Greg joined the San Francisco office of Skadden Arps, the New York powerhouse law firm then riding high in the Wall Street takeover wars of the 1980s. "We pulled all nighters all the time," says Greg. "A lot of Drexel deals. I worked 3,000 hours a year." Actually I should know about Skadden; my brother Nick worked there for nine years. One night in the middle of the roaring '80s, when Greg happened to be in New York on a deal, he was walking the halls at around 11 p.m. when he saw the NICHOLAS SERWER nameplate on a door. "Are you Andy Serwer's brother?" asked Greg. "Who are you?" asked Nick in a none-too-friendly tone (my brother and I weren't on the best of terms at that point). "I'm Greg Raifman from B-CC. Don't you remember me?" Greg asked. "Nope," said Nick, and though he did give Greg an update as to my whereabouts, he clearly needed to get back to work.

Burned out by Skadden, Greg jumped to Montgomery Securities, a San Francisco investment-banking boutique run by hard-charging Tom Weisel. The economy was lousy, but working at Montgomery had its benefits. When Weisel discovered that Greg had taken up competitive cycling, he had Greg nose around to see if there were bike or sporting-goods companies they could do deals with. One day in 1992, Weisel walked into Greg's office and told him, "Grab your stuff. We're leaving in a half-hour." Weisel and Greg popped over to the Oakland airport and flew down to Oceanside near San Diego in Weisel's plane to check out some bike company. After that the two of them hit the surf at Weisel's nearby beach house. Not too shabby.

While in San Francisco, Greg met Susan Rettig on a street corner with a mutual friend. Susan, who grew up in Brooklyn, had gone to Barnard and earned an MBA and an MA in urban planning from UCLA. A go-getter in her own right, she had a career as a marketing executive at Clorox, Sara Lee, and ADP. They married in 1989 and had two sons, Josh and Ben.

Greg and Jon Edwards finally went into business together in 1994, calling their law firm Raifman & Edwards, in that order because "it sounded better," according to Greg. Greg did corporate work and Jon did litigation, and the firm grew to 15 lawyers, including another Georgetown Law alumnus named Tyree Jones. Greg didn't know about the connection, but Tyree and I had both graduated from Bowdoin College, where we pledged Kappa Psi Upsilon.

Years later I'm having an Anchor Steam with Tyree in a bar not far from the firm's old offices on Steuart Street. "It was a busy time," recalls Tyree, who mostly did litigation with Jon. "They did well--not necessarily the greatest managers in the world--and Greg especially always seemed more interested in business than law." Makes sense. The whole Internet storm was building around them.

"At one point you could swing a cat and hit five or six of the hottest technology companies in the world right down here," says Jon. It quickly became apparent to Greg and Jon that the real action wasn't in doing legal work but in actually backing these companies. So in 1996, they formed a venture fund. One of the first companies they helped bankroll was Internet Extra, an early sports portal run by a guy named Mike Schwartz.

"We had invested in Internet Extra and by early '98 we were concerned that it was a failed investment," says Jon, now retired and living near Lake Tahoe, Nev. "I became CEO in April." Greg and Jon concluded that the business was a dog, but that it might make for an interesting play in online media, since the only money the company made was selling and placing banner ads. Within a matter of months they had cut costs, laid off employees, reduced debt, and moved the company to their offices. They renamed the business Mediaplex.

Mediaplex became an online advertising service company. It didn't create banner ads, but it would help, say, Datek Online choose where to spend a million dollars on online advertising. It would buy the spots, and then later, as its technology became more sophisticated, measure the benefits and change the content and placement of the ad. Say you were an airline and you wanted to sell 500 tickets at one price with a banner ad, and after those seats ran out, sell 700 more at another price. Mediaplex's Mojo software could do that for you.

Greg and Jon were working 12-, 15-hour days, running the law firm and Mediaplex. (Forget about seeing the wife and kids.) As the company evolved, Greg took over as CEO. "Basically, they were converting the law firm into an Internet company," says Tyree. "The lawyers moved out, and the tech people moved in."

By early 1999 the business was humming along, and the guys decided to go out and raise $1.5 million in an "A round" of funding. "It was very tough," says Greg. "We were begging for money from friends and neighbors. I remember the first check we got was for $1,000 from some lady in a real estate office in Piedmont. She thought it was big money." Eventually they scraped together the dough. At that point Greg and Jon each owned about a third of the company, which had a total value of some $24 million. That was fine, but all of a sudden the weather began to change.

Do you remember the scene from the movie Mary Poppins, where right before Mary shows up, the wind changes direction and starts to blow, and everything gets strange? That's what happened to Mediaplex in the spring of 1999. "We began to look for another round of money," recalls Greg, "and as tough as it was to raise that A round in February, it was that easy to do the B in May. Guys were calling me up the last day and pleading with me to get in."

After that the VCs came calling, and then the investment bankers. Because Greg had worked as a VC, he was able to keep these backers--which included Pequot Capital, Bain, and Goldman Sachs--from extracting huge chunks of equity. As for the investment bankers, Greg and Jon met with most of them, but they went with Lehman Brothers because it most aggressively pitched for Mediaplex's IPO.

Greg's mom, Grace, happened to be in the San Francisco area for the IPO. On the big day, Friday, Nov. 19, Greg took the morning off; he, Susan, and Grace watched the fireworks together on CNBC. The offering was a smash, and Greg drove in to the office for a champagne celebration. MPLX closed its first day up 141%, at $29.

Within a month the stock doubled, and it kept climbing, and suddenly Greg and Susan were very, very wealthy. "People used to ask me, 'Why do you work?' " says Susan, who was then an executive at SelfCare, a company that sold health-care products online. "And I told them, 'That's what I do.' I never thought about it."

Greg didn't realize it at the time, of course, but his wealth peaked on Thursday, Jan. 27, 2000. On that day Mediaplex hit an interday high of $104, putting the total value of Greg's holdings--including options and shares he controlled with Jon Edwards--at $1.1 billion. A more conservative valuation, not counting the shares he controlled with Edwards, would be $728 million, but in any event, it was more money than anyone could ever imagine." 'Obscene' is what I called it," says Greg's father.

What do you do with a billion in paper wealth? What do you buy? In Greg's case, very little, relatively speaking. He already drove a Mercedes. He owned stereo and computer equipment. He had a bunch of $5,000-plus Serotta bicycles. He bought some more Zegna, Armani, and Brioni. But that was nothing. Greg's only indulgence was a breathtaking, 9,000-square-foot house in Piedmont in the East Bay, overlooking San Francisco, that cost more than $3 million. But still. No jets. No Lamborghinis. No homes in Hawaii.

There were a few reasons for this, some practical, some philosophical. On the practical side, Greg accumulated his great wealth in the blink of an eye. Remember, in early 1999, Mediaplex was valued at $24 million, and Greg's stake was worth $8 million. In less than a year that stake had increased in value 140 times! The interesting thing, though, is that Greg is hardly an ascetic. "He always liked buying things," says Irving. "His clothes, stereo equipment, that kind of thing." What happened was that Greg's situation had vastly outpaced his expectations. He had a millionaire's taste on a billionaire's budget!

Also, although Greg was a billionaire on paper, his wealth was hardly liquid. Far from it. There was no way he could dump even, say, 25% of his holdings without tanking the stock. "It's tougher than you think to sell," says Greg. "Anyway, I wanted to send a message to our investors and employees and hold the stock."

It was within the context of this incredible run that I became reacquainted with Greg. One time he asked me and my wife if we wanted to join him at Le Cirque for dessert in an hour. I declined. I think I had to pay bills that night or something. Then there was the time he came up to my office at Fortune to visit. I remember checking on his stock and writing in my online column about "my high school hurdler buddy making it big." It was Monday, Jan. 31, 2000, the day after Superbowl Sunday, right when the stock was at its peak.

It was during that trip to New York that Greg got on CNN. Actually, I helped set that up for him. Last year I was appearing as a commentator on a CNN show called In the Money, hosted by Terry Keenan and Bill Tucker. One segment of the show featured the In the Money portfolio, a hypothetical portfolio of stocks built and updated by the show's viewers. Every day the show's producers would look for companies in the news, like Qualcomm or Intel, and have the company's CEO or an analyst discuss the stock on the show. Then the stock would be put to a vote: Viewers would go to a CNN Website to give it a thumbs up or down. A certain number of votes was needed for a stock to be added or dropped.

I mentioned Mediaplex to the show's producers and to Terry and Bill, making it clear that I was friendly with Greg and would therefore recuse myself from the segment. And so he showed up at CNN with his entourage--a fairly typical group for a CEO, but it still surprised me.

Greg did fine on the air. He talked about his company with assurance, and he seemed at ease. Afterward we walked out of CNN's New York headquarters, and there was Greg's rented limo. I told him I had a lunch at the Museum of Modern Art with George Bell, then CEO of Excite@Home, and he said, "Happy to give you a ride."

In the limo was Greg's head of marketing and head of investor relations with Palms and notepads, and as we drove up Eighth Avenue they seemed to scribble down everything Greg said. Greg called his mother. "Ma, did you see me? How did I do? ... Okay, great, I love you too. I gotta go." Then one of the other execs called up Mediaplex's office in San Francisco and said into the phone, "Tell everyone to go to CNN's Website and vote for the stock!" Yeesh! I rolled my eyes. This made me uneasy. The lobbying certainly didn't break any laws or even any rules of the show, but it violated the spirit of the exercise. (When we arrived at MoMA, Greg popped out to introduce himself to George Bell.)

As it turns out, Mediaplex mustered enough votes, and the next day the company was added to the show's portfolio. I could tell Terry and Bill were surprised, because to get added a company needed many thousands of votes. Within a matter of days, MPLX was down some ten points, and Terry asked rather pointedly: "This guy was your friend, right?" Yup.

Last spring I mentioned to Greg that I had a friend who ran an online ad agency called SFinteractive in San Francisco. "I know SFinteractive," Greg said excitedly. "How do I get in touch with them?" I gave Greg the number of my friend Bruce Carlisle, CEO and founder of SFinteractive, not thinking much about it. A few weeks later I got a call from Bruce. "Hey, I met your friends from Mediaplex," he said. "What a trip." Bruce, whom I've known since I was 10 (he was my counselor at camp in Maine), is not given to overstatement, so I knew he had a story.

Greg, looking to partner with SFinteractive, went over with a team of executives to that company's offices on Sansome Street. One guy from Mediaplex informed the SFinteractive people that they couldn't afford not to be bought out, because as long as they remained an ad agency their equity would never be worth more than ten times revenue. Mediaplex, valued as a technology company, was worth more like 60 times. "The Mediaplex guys were talking on their cell phones the whole time. They were actually doing other deals," says Bruce, smiling. In the end the two sides agreed on nothing, but the Mediaplex team promised to be back in touch. And so, still glued to their cell phones, team Mediaplex marched out. Bruce Carlisle never heard from them, or Greg, again. "What was so funny is that I remember we had this food out in our conference room, and they ate it all," he says, laughing. "They ate our lunch."

In January 2000, Greg and Susan bought their big house, built in the Mediterranean style and beautifully landscaped, with a large fountain in the back. The ironwork was originally intended for William Randolph Hearst's San Simeon. It all seemed perfect, and the couple readied themselves to move in during the first week of May. Perhaps they should have taken note that the house was built in 1929.

On Monday, May 1, Greg and family moved in. Irving and Grace had come out from Boca Raton. By Saturday the sixth, though there were still boxes lying around, the family was beginning to feel acclimated. That night after dinner, Greg and Grace sat and talked together at the kitchen table until midnight. Yes, the stock was down from $104 to the 40s, but life was still good. Greg kissed Grace good night and went upstairs to bed. "A few minutes later I heard this thud," Greg recalls. "I couldn't understand what it was, so I got up to take a look." What Greg found was horrible beyond words.

"Here's where she fell," Greg says, pointing but unable to look up. It's May 2001 and I'm standing in the stairwell of Greg's home, looking up the main staircase. The noise Greg heard was his mother, Grace, tumbling down the stairs of his brand-new house, crashing her head into the doorway of the library off the landing so violently that plaster was smashed all over the room. Greg found her unconscious in a pool of blood. Greg and Irving were panicked and horrified, but they had to keep quiet so as not to wake up the two boys. (Thankfully, they stayed asleep.)

The medics rushed Grace to Oakland's Highland Hospital. She was still alive, but barely. Doctors discovered she had a Jefferson fracture, which, Greg was told, is a break in the neck so high up in the spinal column that the body cannot breathe on its own. Grace was put on a respirator, but she never regained consciousness. On Monday, May 8, doctors and the family agreed that the situation was hopeless, and Grace was taken off the respirator. She died that afternoon.

As we stood on those wooden stairs almost exactly a year later, I suddenly felt a need for more air. It wasn't just Greg's terrible story that almost made me lose my breath, it was the fact that I had faced the same nightmarish experience of watching doctors take a parent off a respirator to die. It also happened in May 2000. My father, Howard, died five days before Grace, on the other side of the country at Georgetown University Medical Center after a failed liver transplant.

Greg joined me outside the front of his house, and we stood silently in the dark for a while. "Ever since that day," he said finally, "my life went right straight downhill."

From a business perspective, Greg's life had actually begun to unravel a few months before, in February of last year. At that point, with the company still thriving and Greg on the prowl for more deals, Greg and Jon planned a $500 million secondary stock offering. Though Lehman had done their IPO, the company wanted CSFB--a bigger name in this business--to co-underwrite the deal. "When I told Lehman that I wanted to bring in CSFB, they were pissed off," he says.

Greg was concerned that Mike Stanek, Lehman's Internet analyst, was leaving the firm and would be replaced by a junior analyst. Stanek did jump, first to an incubator called Garage.com. But at this point Mediaplex was looking for a CFO, and Stanek decided to leave Garage--after only a few days--and come to Mediaplex. That day, March 9, the stock jumped $5, to $75. Then things got weirder. Greg believes Lehman executives, none too pleased with the situation, began to work on Stanek to return to the bank. Another source says Stanek approached Lehman to come back. Lo and behold, on March 24, Stanek packed up and returned to Lehman.

Over the next two months the stock fell more than 70%. Greg is convinced that with Stanek back, Lehman embarked on a jihad against Mediaplex, calling up institutional investors and trashing the stock. A Lehman spokesman dismisses that as "nothing more than message board blather." To be sure, it could be that shareholders were spooked when they saw a guy like Stanek leave the company. In any event, Mediaplex's stock continued to tank, and as the market worsened for Net stocks, the offering was postponed indefinitely.

On Wednesday, May 17, nine days after the death of Greg's mother, Mediaplex's lockup period for insiders ended. Greg braced himself. Sure enough, whack! On that day MPLX volume jumped from an average of a few hundred thousand shares to 1.2 million as insiders rushed to dump their stock. At the end of the day the stock had fallen nearly 24%, to $25. The slide continued, with more huge-volume days in July. By August, devastation. The stock was at $7. It would get worse, of course. As the bottom fell out of the online ad business, MPLX would fall to $1.

So how much did Greg sell? Next to nothing. Greg's total stock sales have amounted to a few hundred thousand dollars, mostly for taxes, he says. Last summer he unloaded 27,000 shares at $10, for $270,000. This past February he sold 75,000 at around $1, for $75,000. That's $345,000 out of a billion!

Edwards, too, still has most of his shares--though he was hit with a margin call last fall and is now down to six million shares and options. You sure can't say the same about the other insiders. Over the past year they've sold many hundreds of thousands of shares--a disturbing exit by those who are supposedly in the know.

It's April 2001, and Greg and I are having dinner in New York at San Pietro in midtown. I haven't seen him since the market crashed, and he looks different. A bit older. Maybe a bit sadder. I tell him this is a favorite hangout of Ronald Perelman, and he perks up a little, but this is clearly not the year-2000 Greg. "So are you okay?" I ask him. "Yes," he begins slowly. "I just stepped down as CEO." Why? "I just felt it was the right time. I'm still going to be chairman. We brought in this great guy, Tom Vadnais, who worked for IBM." Hmm. I get the feeling that while Greg still cares about Mediaplex--he'll be looking at deals for the company, of course--he's already in search of his next thing.

Where does Mediaplex stand today? It's down, certainly, but maybe not out. Jon left for Nevada. Though he still has his stake, he's no longer even on the board. It's Vadnais' job to save the company. The stock has been hovering around $1, a key threshold, because if it stays below a buck the company could get delisted.

A month later and I'm in Baltimore. It's a cool and cloudy evening, and I'm visiting with Greg's brother Larry, their father, Irv, and Larry's 16-year-old son, Matt. It's a real Maryland scene, in the stands of Johns Hopkins' Homewood Field, at a women's lacrosse match between the University of Maryland and Princeton. We're here to watch the greatest women's lacrosse player of all time, Maryland's Jen Adams, but also to talk about Greg. Adams doesn't disappoint, scoring three goals and assisting in three more as the Terps win 14-7. It's a bit distracting, but the Raifman clan seems both reflective and pretty good at multitasking.

"When Greg's mother died, Greg just buried himself in work," said Irv. "I would go out to visit him, and I would get up at 7:30 just to see him because he would leave so early. And he wouldn't come home until one or two in the morning." Larry shifts uncomfortably in the stands. Still recovering from a terrible car accident in January that nearly killed him, Larry has limited use of his right leg, and his left arm is still in a cast. "I don't think any of this has changed Greg, really," says Larry. "Not the ride up or the ride down. His kids are great, and they're oblivious." Adds Irving: "I'm very proud of him. I told him that his value as a human being has nothing to do with how much money he has in the bank."

What are we to make of Greg and of those phantasmagoric days in 1999 and 2000? Well, Greg is an incredibly hard-working, driven, ambitious, smart guy. There is something about his restlessness, his energy, that drives him in a way I can only imagine. I'm pretty certain Greg will succeed again. Maybe he'll end up with, I don't know, $50 million in the bank. As for another billion, I don't think so. Whatever you make of Mediaplex, this much is clear: Greg and his company were swept up in one of the greatest bubbles in the history of commerce. How out of whack did things get? In Greg's case, we actually have a metric (as they used to say!). Remember, his Mediaplex stock was worth some $8 million in early 1999. Then it climbed to a billion. Today it's just under $8 million. Yes, Greg has some other assets too--tech stocks mostly!--but essentially he's right back where he started. You could argue, therefore, that the Internet bubble threw things out of whack by a factor of 140 times!

So what is it like to make and lose a billion dollars? "I won't kid you," says Greg. "It hurts watching the stock go down day after day. For us and for investors and employees. Sure, we're doing just fine, but people who say, 'Oh, you have $5 million or $10 million, that's the same thing,' are wrong."

There are many people who wish they could just wash away the past three years. Pretend they never happened. I know both Greg and I feel that to an extent, but mostly that's because of the deaths of our parents. Aside from losing Grace, in many ways Greg is better off than he was three years ago. For one thing, he's spending time with his boys and Susan. The dot-com she was working for has gone belly-up, of course, but they are making their mortgage. And then there's the experience factor. With the stuff Greg's seen and been through, well, you could write a book, or at least a magazine article.

REPORTER ASSOCIATE Julia Boorstin

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