38. Jessica Reif Cohen

Reif Cohen didn't plan on becoming one of the preeminent media and entertainment analysts. "I wanted to get into sales," she says, but was hired by what is now investment bank Natixis Bleichroeder. "It was a complete fluke." Since 1994, the Brooklyn native has worked for Merrill, which Bank of America will acquire next year, leaving her future unclear. For now, her work lets her indulge in worldwide travel, visiting units of companies she covers in Asia and Australia. In January, Reif Cohen and a few others turned bearish on media stocks, a prediction that has come to pass. But sometimes work has a ripple effect at home: Her 12-year-old daughter loves "Hannah Montana" and the Jonas Brothers -- which recently caused a rift when Mommy downgraded shares of Disney.