Meet the Facebook Mafia

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Peter Thiel

Thiel's résumé includes many of the darlings of the social Web: He was CEO of PayPal, a LinkedIn investor, and one of the earliest backers of Facebook. He remains on the Facebook board and maintains a 2.5% stake, which could be valued at up to $2.5 billion after the IPO. His newest ventures are far more eccentric. Recently, Thiel invested in biotech start-ups looking to reverse the aging process and Blueseed, a moored boat that will float in international waters and serve as a business incubator. Thiel's Founders Fund also flew 50 engineers and entrepreneurs to Hawaii for a secretive three-day conference.