Robin Williams — Aladdin: His role as the genie in the animated film Aladdin in 1992 was instrumental in establishing the importance of star power in voice actor casting. It didn't come without a price, though, as Williams and Disney had a bitter falling out over his name or image not being used for marketing, which Disney did anyway.
Ellen DeGeneres in Finding Nemo — Dory: For his bubbly fish story, writer-director Andrew Stanton paired Albert Brooks' depressive Marlin with DeGeneres as the perky, amnesiac Dory. The comedienne's stumbling speech pattern means her dialogue sounds true to herself and Dory.
Cameron Diaz in Shrek — Princess Fiona: The scene where Princess Fiona burps was written after a recording session where Diaz burped after drinking a fizzy soft drink. Diaz is joined by Eddie Murphy and Mike Myers in Shrek.
Tom Hanks in Toy Story — Woody: A blockbuster feature about a child's bedroom full of toys with minds of their own. Hanks is the cloth cowboy Woody, alongside Tim Allen as the more modern Buzz Lightyear. The expert exasperation Hanks put into his '90s roles well suited him for Woody, especially when he must provide tough-love psychotherapy to Buzz, who thinks he's an actual space hero.
Jack Black in Kung Fu Panda — Po: According to his online diary, Jackie Chan recorded his voice-overs during a single five-hour recording session in LA. Black said he has never had so much fun in his life.
Samuel L. Jackson in The Incredibles — Frozone: Jackson was cast as the voice of Frozone because producer Brad Bird wanted the character to have the coolest voice.
Angelina Jolie in Shark Tale — Lola: She joined a host of actors notably Robert De Niro and Martin Scorsese, Will Smith, Jack Black and Renee Zellweger who all recorded their lines together.
Ben Stiller in Madagascar — Alex the Lion: Along with Chris Rock as Zebra, David Schwimmer as Giraffe, Alex is holed up at New York's Central Park Zoo in search of adventure.