Taboo is definitely one of my favorite games, and it is simple to play. Players divide into teams and one player, "the reader, " tries to get his or her teammates to guess a word printed on a card. The twist is that also listed on the card are taboo words that the reader is not allowed to say.
A person from the oppostite team watches the reader to see if any of the words are said and pushes a buzzer if they are. The reader loses a point for his or her team and has to continue on to the next word if buzzed, but if the word is guessed correctly with no buzzes, the team gets a point. It's crazy what some people come up with to explain, for example, a house, without saying the words building, window or door.
It's an especially fun game to play with people you know well, because all the inside jokes come out. Then again, it is also a good icebreaker for people you have just met. The game can be as short or long as time allows. All ages can play.