Mark Cuban is one of the original Internet millionaires. He founded Broadcast.com along with a friend in the mid-1990s and made a fortune selling the company to Yahoo during the dot-com boom years. Since then, he has continued to keep his eye on the future of technology, founding HDNet, the first national network to broadcast all of its programming in 1080i resolution, the highest-quality format of high-definition. When he's not planning for the future of HDTV, he spends his time running his NBA franchise, the Dallas Mavericks, and will star in a reality show debuting on ABC on September 13, called The Benefactor.