27. Chris O'Donnell

Last time here, CHRIS O'DONNELL showed off one of his hidden talents -- karaoke! When he's back today, Ellen's finding out what else he can do! ASHLEY TISDALE has grown up from "High School Musical" -- now she's on the popular new show, "Hellcats," where she plays the captain of a cheer squad. She'll stop by and might have a routine to teach Ellen!