6. MicrosoftMicrosoft's ( MSFT) attempts at social networking have never been anything noteworthy, but investors have to laud CEO Steve Ballmer's decision to buy part of Facebook. In 2007, Redmond, Wash.-based Microsoft purchased 1.6% of the social networking giant for $240 million, which gave Facebook a whopping $15 billion valuation. Facebook's value has increased fivefold since then. Microsoft is selling 6.56 million shares of the 32.8 million Facebook shares it owns. At the mid-point of the IPO price ($31.50), Microsoft stands to make $206.5 million, nearly recouping its initial investment with more than 26 million shares left. Shares of Microsoft have gained 18.07% this year.