Celebrity Cartoon Voices! Who's Your Favorite?

On July 29th, Katy Perry will make her animated debut voicing a Smurfette in The Smurfs. "I feel like a walking cartoon most of the time, anyway," Perry told USA Today of her role. The California girl joins a long list of stars who have lent their voices to animated characters, from Angelina Jolie's Tigress in Kung Fu Panda, to Emma Watson's turn as a princess in The Tale of Despereaux. Click through the gallery to see the stars behind some of our favorite cartoons!