Discovery Channel's Greatest American # 18: Bill Gates

This one's pretty hard to argue with, as wrongheaded as Gates' politics are.

Like it or not, Microsoft fundamentally changed the way we work. When Bill Gates built his first disk operating system, work in America was largely blue collar. Now it is largely white collar. The reason for this is Microsoft Windows.

Can you imagine a world without Windows? Mac snobs fancy they can, but for the teeming multitudes, it is literally inconceivable.

And besides that, Gates is richer than Croesus.