Pick as numerous cards as you've players. Select one ace & one king and mix within the deck till you deal one card to every player. Players have to memorize their card. The person with the ace is the "drug dealer" and the person with the king is the "cop".
The "drug dealer" have to wink at the other players. Any person who sees the wink have to say "The deal is done." It's up to the "cop" to work out who the dealer is. For every mistaken guess, the "cop" have to drink. Players can bluff and pretend they saw the wink even when they have not that makes it much more fun.
This really is fun with large folks since it is harder for the cop to guess. Though, if the cop sees the wink, the "drug dealer" must drink.