Despite tough fundraising times for venture capitalists, the web browser pioneer (Mosaic, Netscape) raised $650 million this fall -- over just three weeks -- with partner Ben Horowitz. That's on top of the $300 million the two raised earlier this year. Among his two-dozen portfolio companies: Digg, Foursquare, Skype, and Zynga. Already on the boards of Facebook, eBay, and Hewlett-Packard (where he took a leading role in ousting CEO Mark Hurd), Andreessen looks to take a board seat anytime the company invests north of $5 million.
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