(FORTUNE Magazine) – Consider this: If the more than 100 billionaires examined on the following pages liquidated all their assets, they could comfortably eliminate the 1987 U.S. budget deficit. Dream on, Gramm-Rudmanites: The world's billionaires can't cash out, at least not in dollars. Their $255-billion net worth exceeds U.S. currency in circulation by more than $30 billion. The vastness of the wealth commanded by the people in this special report is staggering indeed. But that alone would not have propelled FORTUNE from Brazil to Brunei and back again in an effort to locate the lot of them. We thought it important to identify this group because of their power. Two are Queens; six are heads of state. Those who do not run countries tend to run companies, thousands of them, which in turn employ millions of people. They influence what we eat, what we wear, how we heal ourselves, and how we defend ourselves. They sway politicians, and sometimes make or break them. Money speaks, but it also hides. Swiss bank accounts and shell corporations are timeworn ways to obscure wealth, and many of the world's very richest have cultivated an understated style to thwart the tax man -- and the list woman. Says Pittsburgh billionaire Henry Lea Hillman: ''It's the spouting whale that gets harpooned.'' Ambitious in scope, FORTUNE's list is not exhaustive. We missed laundered money and flight capital -- untold billions belonging to a bunch of someones somewhere. We didn't try to catch the crooks, though we do report on a few. And some upstanding rich folks surely escaped our data-gathering net. But after almost a year of duly diligent reporting, we are convinced it is the most comprehensive list of great wealth ever produced. Tracking down billions -- even making them -- could be easier than grasping what a billion means. ''Billionism,'' mused Oliver Wendell Holmes in 1861, ''must be a blessed kind of state.'' As metaphysical as it is physical, billionism is better understood in terms of time and space than quantity. Think of it this way: A billion dollar bills placed end to end would wind around the earth four times. Booking a billion miles would be the equivalent of five round trips to the sun. A billion minutes ago, the Colosseum had just been built in Rome. A billion is to a million what a million is to a mere thousand. A million minutes ago, the Kansas City Royals were winning the 1985 World Series. And millionaires are relatively commonplace these days, with more than a million of them in the U.S. alone. But becoming a billionaire is still the stuff of dreams. Women -- not just Queens -- are allowed in the billionaire's club; they make up roughly 10% of the list. The booming stock market has multiplied the number of hyperhaves. Among the newcomers is William Gates, whose 40% stake in Microsoft, the computer software company he founded, swelled to the billion- dollar mark last March. Just 31, Gates is the world's youngest self-made billionaire ever and certainly Harvard's richest dropout. Most billionaires are not as newly minted as he, but an impressive number have made their money since World War II. They did it the hard way, starting at the bottom in jobs like servant, truck driver, and cabaret singer. Billionaires have sprung up in 20 countries, a highly uneven and in some cases curious distribution. The U.S. leads the billionaire brigade with nearly half the entries. No surprise. But Switzerland, of all places, doesn't rank -- perhaps because its secrecy laws make hiding wealth about as easy as spending it. Arab nations have produced a dozen billionaires, and Asia ten. Britain, West Germany, and even the Netherlands each claim six. Perhaps the biggest surprise: Three of the world's ten wealthiest clans are Canadian. Just as most soil is fertile ground for billionaires, so are most lines of business, from potatoes to pharmaceuticals. The highly fecund fields include the media, real estate, oil, retailing, food, and finance. Some billionaires had great wealth heaped upon them through inheritance. Allah has been kindest to the Sultan of Brunei, the richest man on earth, who was born to rule a tiny oil-pumping station on the island of Borneo. He shares his 1,788-room palace with two wives and nine children. Billionaire bachelors like Bill Gates and David Koch, 47, are in the minority. The world's most eligible, alas, are outnumbered by those who are attached, sometimes to people much younger than they. Prince Johannes Thurn und Taxis, a 61-year-old West German, is married to a countess 30 years his junior. Some billionaires are in their twilight years, but most have ample time yet to multiply their bounty and spend it vigorously; their median age is about 61. Being a billionaire means being able to afford things that are priceless. Among the favorite artists: Monet and Michelangelo. The car of choice for several of them is a Ford, albeit the fanciest of Fords, the Aston Martin Lagonda. Plying the slopes, playing whist, and gunning for quail seem to be the sports of billionaires. Of course, there are also the tightwads -- folks like ''just-call-me-Mr.-Sam'' Walton of Wal-Mart fame, who drives to work in a pickup truck, and Queen Elizabeth II, who scurries around the palace turning out lights. Having enough money to buy the entire stock of Tiffany's 15 times over does not ensure peace at home. Billionaires seem to bicker as much as ordinary folk, and sometimes sue siblings for hundreds of millions of dollars. But the norm is the close-knit clan, billionaire brothers like New York's Tisches, who sometimes share a limousine, and Chicago's Pritzkers, who share their corned- beef sandwiches. What sets these people so far above run-of-the-mill multimillionaires? How can you too ascend to billionism? Step No. 1: If you make candy bars, try throwing them against the walls once in a while, as Forrest Mars used to do, to make sure they're always absolutely fresh. Step No. 2: Work like hell. As billionaire brewer Alfred Heineken says: ''Anyone who doesn't know what it means to have painful feet doesn't know what selling is.'' Step No. 3: Turn to page 120 and start reading. The billionaires have tales to tell.