Founder, Wikipedia; Chairman, WikiaRank: 13Why he matters: It may not be 100 percent accurate, but Wales's user-generated Wikipedia has become the first place we go to learn the basics of just about anything. Yet as the scope and influence of Wikipedia continue to expand, Wales has been concentrating on Wikia, his for-profit company -- backed by a reported $14 million in venture funding -- that seeks to extend the wiki concept into ad-supported, user-generated community sites.
Wales is also working on a people-powered search site that would rely on human intelligence to do what Google's proprietary algorithms can't. Some think Wales is nuts to challenge Google, but the notion of building an online encyclopedia with an army of unpaid volunteers once seemed crazy too.
Meet 50 Who Matter winner Gina Bianchini. Her site, Ning, lets anyone be a social networking mogul. (more) 
