45. Eileen Oneill

She goes by the nickname "Peppermint Patty," but that's more due to her freckles than her temperament, which she describes as "easygoing." Such a personality has served O'Neill well in her 17-year career at Discovery Communications, which started with a grad school internship. This year she spearheaded the launch of Planet Green, which went live in June. In July, she moved to TLC "to reinforce the TLC brand and build out from shows like 'Jon & Kate Plus 8' (which O'Neill developed while at Discovery Health) and 'Little People, Big World.'" Unsurprisingly, O'Neill's house is packed with CFL lightbulbs, and her garage houses a hybrid car. In 2009, she's hoping to bring a little green to TLC's content choices, too.