Paul G. Allen - $17.5 Billion
Paul G. Allen, the co-founder of Microsoft, invested some of his money like other billionaires -- he bought sports franchises. He owns two professional sports teams, the Seattle Seahawks and the Portland Trail Blazers. He is also part-owner of the Seattle Sounders FC, which joined Major League Soccer in 2009. Allen is also the founder and chairman of Vulcan Inc., which manages his various business and philanthropic efforts, as well as the founder of the Allen Institute for Brain Science, the Institute for Artificial Intelligence, the Institute for Cell Science and Vulcan Aerospace.
