A simple game with a pretty high buzz factor. Simple supplies: people, beer,
deck o' cards.

One player goes first. Using mental telepathy, s/he tries to predict the color
of the card about to be turned over. If correct, s/he continues; if incorrect -
drink.

If correct three times in a row, the player can make a rule concerning
procedure for the game. Interesting rules are:

"Can't say red"
"Can't say black"
"Tap head before drinking"
etc.

As always, be creative.

Of course, if some is caught "violating" a rule, s/he drinks. But be sure not
to break the rules while enforcing them.