How about being Beetlejuice for Halloween. I mean, if you're going to be some sort of monster/zombie, you might as well be a nice one, that has movies based after him.
If you wan't to go all out, this might be the way to go. The biggest problem is that to stay in character, you'll have to perfect the "yell" and only use it the entire time. Everything you see in the picture is included
He's all of our favorite bounty hunter and probably the scariest person a live. I don't think I can think of anything more terrifying to be for Halloween.