A good example would be Dave Cummings, former KCBOT trader and founder of TradeBot (an automated trading firm) and BATS (an electronic stock exchange that's grown very rapidly over the past few years). He's actually moved into venture capital recently (http://www.tradebotventures.com/).
ETA: Though to be fair he does have an engineering background. Some others I can think of (e.g., guys who founded GETCO) don't.
But I still feel a twinge of regret when I read these articles. I'm skeptical about the value of these activities. I don't think they contribute much to the general wealth (the contributions may even be negative) and I definitely share in the resentment many people feel these days toward the banking industry.
A lot of folks try to equate this with a resentment of wealth or capitalism, but I think that's incorrect. Americans still greatly admire people who become wealthy, and generally don't view the economy as a zero sum game. For instance, nobody (almost) resents the millionaires and billionaires at google. While I'm not sure if your average American has thought it through this carefully, I think it comes down to the perception that startups create wealth, whereas wall street takes wealth.
That's too simplistic, I know. But I don't think it's entirely incorrect, either.
I guess I'm just a little sorry to see geeks displaying the behavior I always associated with suits - involving themselves in activities of dubious economic value for the sole purpose of enriching themselves. Especially when geeks have so many ways of becoming wealthy that also add tremendously to the general wealth.