ooh, so far I havent thought about it, but more time to plan means more time to get ready. I would love to do a haunted castle theme actually :) but I may be moving at the time so I will update when I find out! Great topic and can't wait to see what other people are planning!
Oh, actually come to think of it, even if I am moving I can probably pull off a Clue House ha :D
I am trying to think of a theme... last year it was someone famous or historical who was dead. This year so far ideas are: so far we have classic costumes (witches, vampires, werewolves, etc.), film stars, tv show characters, superheroes, and celebrity death watch list (Lindsey Lohan, The Biebs, Courtney Love, etc.).