"I'm in prison, but I'm on just the same playing field as Warren Buffett,"

Curtis Carroll discovered the stock market in prison. Through friends and family on the outside, he invests from San Quentin State Prison in Northern California, and he's also an informal financial adviser to fellow inmates and correctional officers. Everyone in prison calls him Wall Street.

"I couldn't believe that this kind of access to this type of money could be accessible to anybody. Everybody should do it. And it's legal!" he says.

He pores over financial news: the Wall Street Journal, USA Today, Forbes. Business is like a soap opera, he says, and he's always trying to anticipate what will happen next. "I like to know what the CEO's doing," he says. "I like to know who's in trouble."

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