Should Zach Galifianakis ever grow weary of starring in 'The Hangover' movies, his musical doppelganger Zac Brown could fill in without fans knowing the difference. Of course, we're not sure the singer has the comedic chops of the actor, but Zach G. probably can't play a guitar like Brown, either. We actually prefer Brown's beard, as the one featured on the 'The Hangover Part II' poster seems glued on.