I'm insanely intrigued by Elon Musk, the CEO of Tesla Motors and SpaceX. The guy is only two years older than I am, but he has managed to change the world. After cashing out as the largest shareholder of PayPal, he went and started an electric car company, and a commercial space company. Can you think of any two more ridiculously hard things to do? I would argue that these are two of the most important new businesses in the world right now because they dramatically challenge the status quo and improve the world.
Musk could have just retired and sipped fruity drinks on the beach for the rest of his life, but it doesn't seem like money particularly motivates him. If it did, I don't think he would have taken the risks he has with these new businesses. He's taking on Detroit with one, and giant companies completely integrated into the industrial-government complex. Neither has had to try all that hard to innovate (though this indifference nearly killed the auto makers).
It's interesting that these really big bets, requiring a lot of money, come a lot easier if you've already won. I'm not sure you could endeavor into these industries at all without all of that money, but at the very least you're certainly less likely to try without having already achieved success.
I'm surprised to realize that success can buy you a lot of freedom to take greater risks. I might even say that they're not even risks at that point. I mean, think about it in a scale normal humans can understand. If you busted your ass to save everything you could and bought a very modest house with cash, at that point, your expenses are pretty easy to meet. You can try anything without any serious risk to your wellbeing.
It's exciting to think about, and I'm glad that others are taking the big risks to move us forward.