Bill Gates. What can be said that hasn't already been said? Has any modern day businessman been more vilified and loved at the same time. The man is the richest person in the world, worth more than the GDP of over 100 nations with an estimated fortune of $70 billion US (as of November 2000). If anything he's Richie Rich.
With an aggressive, winner-takes-all attitude, he transformed Microsoft, a small niche company, into the most influential company in the computer industry and the world for that matter. He's driven, intelligent and doesn't apologize for the fact that he can take you down in a flash.
"In this business, by the time you realize you're in trouble, it's too late to save yourself. Unless you're running scared all the time, you're gone."