Amanda Bynes

Biography: When this multi-talented actress landed her own eponymous variety show at 13, she'd already graced the small screen for three years on Nickelodeon's sketch series All That. Despite her model's looks, Bynes is given more to do than a typical ingénue because of her solid comic instincts and precocious knack for physical humor. In the early 2000s, Bynes graduated to the big time (even though she had yet to finish high school) with a leading role in the movie Big Fat Liar and the prime-time sitcom, What I Like About You. And if she hadn't done so already, at 23 she shed her child-star image (and most of her clothing) by posing in lingerie on the February 2010 cover of Maxim magazine.