10. Matthew Lillard
Worst Performances: She's All That (1999), Wing Commander (1999), Thir13een Ghosts (2001), Without A Paddle (2005)
Somebody hand this man a Valium. To ever-irritating effects, the tall, loud, and awkward Lillard pisses on subtlety whenever a camera is pointed in his direction, contorting his face and spewing dialogue like a clown on speed. He's like a real-life cartoon character, only one that you'd switch the channel for in favor of American Dad. Who even watches that show, anyway?