25. Christina Aguilera
Occupation: Singer, Actress
The former Mousekeeter and bubble-gum pop star left that persona in the dust when she reinvented herself in the video for "Dirrty," and appeared nude on the cover of Rolling Stone. In the transition from good girl to bad girl, she dyed her hair black, called herself "Xtina," which she got tattooed on the back of her neck, and got some piercings.