Christina Aguilera

A former star of The New Mickey Mouse Club who hit it big with an innuendo-laden single, then traded in her implicitly not-so-good-girl image for an explicitly not-so-good-girl image. Where have we heard this one before? The child of an Ecuadorian-American father and a Caucasian mother, Christina Aguilera started her career as a professional performer at age ten with a 1990 appearance on Star Search. Her subsequent Mickey Mouse Club stint led to Disney using her "Reflection" on the 1998 Mulan soundtrack, and RCA released her self-titled debut in 1999. Dance-pop smashes like "Genie in a Bottle" and "What a Girl Wants" showcased her big voice, which, along with her Spanish-language version of the album (Mi Reflejo), set her apart from the late-'90s crowd of pop-star ingenues.

Yet Aguilera was still coming in second to Britney. Her appearance on the sexy 2001 remake of "Lady Marmalade" suggested a way into the spotlight. She radically altered her image for 2002's Stripped and became Xtina, widely mocked for her look even as her voice proved soulful and mature. But in 2006 she released the acclaimed Back to Basics, a tribute to the jazz and soul she says inspires her, and cemented her status as a grown-up diva.