February 16, 2012, 8:00 AM —
Founder & CEO Mark Zuckerberg: $28 billion
Mark Zuckerberg, 27, was rich before Facebook's IPO, but now the Facebook founder and CEO becomes insanely rich. Thanks to his 28 percent stake in the company, Zuckerberg could be adding up to $28 billion to his bank account. Not too bad for a Harvard dropout.