(FORTUNE Small Business) – It would be hard to make the case that Jared Polis is typical of the entrepreneurs who populate this year's Big Ideas list. For while others stand poised on the verge, he has already crossed over to the other side. Polis founded BlueMountain.com, an Internet offshoot of his parents' greeting card company, while he was in his early 20s. You can guess the rest of that story, though the magnitude of the numbers involved has likely regained its power to shock: He sold out for a cool $780 million, nearly half in cash. He was all of 24.

Well, that's how the world worked back in 1999. You remember; he does too, and many years from now when he's old and graying--say, 35--he might want to portray it as a golden era for business builders. But right now, like everyone else on this list, he doesn't have much use for what was. He has to focus on what is. And while that's hard for anyone who lived through the boom--never mind someone who profited so irrationally from all that exuberance--it may actually be easier for Polis, whose world is sharply divided between then and now. Thanks to his youth, he's really only known the economy in two different moods: boom and--well, he'd never label today's environment a bust.

Polis prefers to say that his new venture, a chain of Spanish-language movie theaters called Cinema Latino, operates in a climate that is "more thoughtful and deliberate" than what he saw at the e-volution. That's not just his way of saying everything's cheaper, although it's certainly true. "During the 1998-99 era, a ridiculous premium was placed on top-line growth," explains Polis, who adopted his mother's surname in 2000; before that he was Jared Schutz. "That trend had a pretty crazy effect on businesses. Now you have a more rational business-planning environment. You can actually take the time to get it right." Polis concludes, "This type of environment is a better one to start a business in, and what we had before was a better one to sell a business in."

He's not the only one who thinks so either. Real entrepreneurs (translation: the ones left since the stock market tanked, the economy slipped, and the bubble burst) have always behaved as if the driving force behind any successful business had to come from within: the passion for the idea, the drive to execute it perfectly, the desire to dominate (even in the face of giant competitors; see "Darius Bikoff vs. Coke and Pepsi," page 60). That's why so many of them (Dell, Microsoft, Motorola) have gotten off the ground during periods that look utterly bleak to outsiders. Entrepreneurs are supposed to think in original and creative ways, remember?

If you had forgotten, then the 14 companies featured on the following pages ought to serve as useful reminders. These folks aren't kidding themselves. They plainly understand which way key indicators like consumer confidence are pointing. But they've managed to raise money by having a good story to tell (for a company that tells amazing stories, see "Inside the Pixar Dream Factory," page 44). And they know instinctively why now is the time to hunker down and build a business: You're spending less, at a juncture when the market is poised to expand. "It doesn't matter what business climate you're in," says G.T. LaBorde, co-founder of MedMined, which helps hospitals keep track of infectious outbreaks. "If you have a service that really does deliver the value that you claim, and the value is measurable in real dollar returns, that is something you can probably sell in lots of different business environments."

Better times breed more startups but not necessarily a higher quality of them. According to the Global Enterprise Monitor (GEM), an annual survey published by the Kauffman Foundation, an entrepreneurial think tank in Kansas City, at the peak of the boom in 2000, actual or would-be entrepreneurs made up a very fluffy 16.6% of the U.S. population. A year later, in 2001, the index was off by more than one-third, at 10.5%. And the latest figure, released in November 2002? Ten percent, or essentially unchanged. To Larry Cox, the Kauffman's director of research and co-author of the GEM study, that leveling-off suggests there exists in the U.S. a hard core of imaginative entrepreneurs who are unfazed by current conditions. "Even in 2000, you had entrepreneurs pursuing solid, profitable ideas," says Cox. "But you also had this group that was jumping in with business models that didn't make any sense. I'm hoping that we've returned to a level that represents good, solid businesses pursuing excellent opportunities."

Returned, as well, to a set of conditions that, while new to youngsters like Polis, feels a lot like the old days to more- experienced entrepreneurs. One key feature: a vastly reduced role for venture capitalists. As the ranks of entrepreneurs have thinned, so too have the ranks of VCs, whose numbers are expected to bottom out at two-thirds of peak levels by the middle of the decade. In dollars and cents, the decline is even more dramatic: $4.5 billion invested during the third quarter of 2002, according to PricewaterhouseCoopers, compared with $29.2 billion in 2000's third quarter.

No mystery here. Ever since IPOs went on the endangered-species list, VCs have been reluctant to commit funds. Even when they can be persuaded, they're putting the squeeze on valuations. The news isn't all bad. If you want funding for a B2C or a B2B, good luck (you'll need it), but sectors like software, telecom, biotech, and medical devices are pretty hot. Moreover, VCs and angels insist, there are benefits to the reduced flow of capital: namely, the potential for a closer, longer-term relationship between companies and their backers. Many new VCs are former entrepreneurs who made their money during the boom and so bring to the table operational experience, not just financial know-how. And if you're not happy with the low valuations being offered, well, look at it this way: At least the odds of getting hit with a dreaded "cram down"--an even lower valuation in a succeeding round--are diminished.

The key word is patience. "i haven't really been obsessed with exit as such," says Big Idea entrepreneur Dan Lifton, co-founder of Rubberworks, a tire-recycling venture. "I think the focus now is more on organic, controlled growth--build to prove yourself, then scale up." Which is by no means a bad way to grow; it's just different. In the old days the challenge was short-term survival in a landscape crowded with venture-backed competitors obsessed by top-line growth, and willing to spend almost anything for it. Now the object is long-term survival in a barren landscape, which puts the emphasis squarely where most serious entrepreneurs like it: on building a company that will last.

Once you've made that adjustment, successful entrepreneurs say, the real advantages of operating in today's environment snap into focus. "I have been able to negotiate with all service providers--banks, lawyers, landlords--to get very good deals," says Gloria Ro Kolb, founder of Fossa Medical, whose device for aiding in the removal of kidney stones recently received FDA clearance. "They are all hurting for business." At MedMined, which is hiring now, LaBorde says it has benefited from the soft job market caused by the recession: "There are good people looking for employment because of current conditions, and we've been able to find some of those." And at Internet florist Proflowers, another of Jared Polis's ventures, customer acquisition costs have come way down, thanks to the collapse of the Internet advertising market. "It's starting to recover," says Polis, "but it's way below what it was in 1998-99, when the only way to acquire customers was at these outrageous costs. Now we can actually acquire customers at reasonable costs."

Doubtful? Join the club. In today's environment skepticism reigns. Consumers are suffering from gizmo fatigue and innovation overload (though there's still a big payoff in listening to them. See "Building a Company Warren Buffett Would Buy," page 51). Big-company purchasing agents have returned to their traditional skittishness over new and untried names. Investors are deeply suspicious. "Whenever we hear someone say these days, 'You don't get it,' we know who doesn't get it," says consultant Jim Geisman, who spent ten years presiding over the fabled startup clinic at MIT's Enterprise Forum, "and it's not us." If you've got the Next Big Whatever, keep it to yourself. "The day of the fake entrepreneur has faded away," says Grant Heidrich, a partner with Mayfield, a Silicon Valley venture fund.

But the Big Idea hasn't gone anywhere. It's still out there, waiting for a person who possesses the patience to figure out how best to turn it into a business (Can it always be made into a profitable business? See "A Killer Idea," page 56), and the passion it takes to follow through. Sure, that takes time. But even Polis, who played his hand beautifully at the height of the boom, says this method of company building is "much more fun." Which suggests he may not be such an oddball after all.

For Big Idea entrepreneurs, it's never just about the money. That's why there are so many of them out there. Still. James Geshwiler, managing director of CommonAngels in Lexington, Mass., a group of angel investors, hears from them all the time. "I'll get an e-mail from somebody who's got a new address, and I'll say, 'What's up?' And they'll say, 'Well, I'm starting a company.' And I'll say, 'Why?'" he says. "And then this phrase comes up, which I hear time and time again from entrepreneurs--'I can't help myself; I have this idea.' To that entrepreneur, everything else is irrelevant." Such visions confirm the enduring power of the Big Idea.