Microsoft CEO
Bill Gates is worth more than $30 billion, thanks to his 12.3% stake in a resurgent Microsoft, whose Windows operating system dominates the desktop on 90% of the world's PCs. Gates' empire extends to Internet access (MSN), television (MSNBC and a stake in cable giant Comcast), computer games (Xbox) and even philanthropy (the $24 billion Gates Foundation). Gates, 46, was slow to recognize the importance of the Internet. But with his ambitious .NET initiative — and diminished pressure from antitrust regulators — the world's richest man may end up dominating a whole new realm: cyberspace.