4. Jackie Earle Haley/Clint Howard
Both are short, balding and have crazy eyes that scare children. Haley recently returned to acting after a 13-year hiatus with films Little Children (still scaring kids) and The Watchmen. Clint is Ron Howard's brother, but is best known for having bit parts in every '80s movie, ever.
More bonus look-alike fun: Jeffrey Dean Morgan, who plays The Comedian in The Watchmen, looks an awful lot like Javier Bardem - at least when he's not rocking a Prince Valiant and carrying a cattlegun.