A simple game that requires a little bit of thought. Standard supplies: people and beer.
Any player can start the game, all it takes is the calling out of a category. The next player then has to say some that fits into that category. Play ends when somebody repeats something that has already been said, or can't think of anything new. The player at fault takes a drink, then play starts again with a new category.
Sample categories: States, Cars, Brands of Beer, Sexual Positions, Brands of Cigarettes, Animals, Colors, etc.
This game may be the inspiration for those lame, mass-marketed beer brands' pot-shot commercials targeting "generation-xers" where they sit around and start a category like "Gilligan's Island, or "Music of the 70's."