Wall Street seems tough on companies that have a deep-seeded social vision-Ben & Jerry's being an extreme example. Traders don't care how much good you think you're doing. They want to see you make money-any extracurriculars that cut into profits are considered a waste.

In Red Hat's case, the company's philosophy-and all of its success so far-stems from the Kool-Aid of the open-source model, the almost moralistic belief that freely available source code is good for business and society. But that's a hard line for Wall Street to swallow, and it has implications that bankers aren't going to like.

For example, Red Hat might be the first public company that's downright afraid to dominate its industry. Doing so would violate open-source principles and alienate Red Hat's strongest base of support-the company says so in its SEC filing. But will investors react to a company that puts limits on its growth?

So far, everyone's happy. Goldman Sachs obviously believes in Red Hat enough to underwrite the IPO. And Red Hat is still down with the Linux 'hood. A Linux World online poll, as of June 13, showed 33 percent of respondents planned to put money into Red Hat stock.

Red Hat needs street cred to keep its business growing. Among the risk factors listed in its S-1 filing is the possibility that expansion plans might disgust the Linux faithful. The company has even managed to begin advertising and "branding" itself-both acts of treason in some programmers' eyes-so far without upsetting too much of the Linux community.

But a public company can't be happy just making money; it has to make more money, keep the top and bottom lines growing year after year. Linux happens to be hot right now, and the big names like Sun and IBM are falling over each other to join the parade, but what happens when growth slows? To a Wall Street spoiled by Yahoos and Amazon.coms, that's a catastrophe.

Hopefully, Red Hat executives are steeling themselves for all this. They did chase down venture funding, which probably means they had an IPO in mind. (As one unhappy chief executive officer told me, "The first minute-the first instant-that a venture capitalist shows any interest in you, it's because he's found his exit strategy.") And Red Hat won't be alone on the market: With ".com" IPOs losing luster, open-source software is bound to be the next fad, as companies like Caldera and VA Linux Systems prepare to take the plunge. Those deals will make good money for some deserving people, and I wish them all luck. But I wouldn't want to be in Red Hat's shoes when things turn from great to just good, and the shareholders start screaming.