I throw a Halloween party every year and we always try to play some appropriately themed game. Werewolf, Last Night on Earth, Betrayal at House on the Hill, or Resistance.
We played Cash n' Guns this year and I saw Gandalf the Grey pull a gun on Steve Jobs who was targeting a man dressed as Flo (from the Progressive commercials). Flo had to bail because Frodo Baggins and Bob Ross had him/her in their sights as well.
When I set up Advanced Civilization, I set up a side table with all the Civilization Cards...and one or two of those torch lights (where a fan blows up a fire-shaped fabric so it looks like a flickering flame).
If anyone turns up inebriated, I shove out of print games out of sight. My best friend's wife is a little too fond of the sauce - and rather clumsy with it. No one's giving my Fury of Dracula a bath in red wine.