Meet the Facebook Mafia

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Sheryl Sandberg

The former Treasury Department chief of staff and Google vice president made news recently about her insistence on leaving work at 5:30 every day to spend time with her children. Although the Facebook COO has yet to found her own company or invest heavily in other start-ups, the upcoming IPO will give her more than enough to do either—with almost 2 million shares, her stake will be worth roughly $1 billion.