Hmmm, apparently nobody has written about Beirut yet. Well, then.
Beirut (also known as beer pong, though never in the company of a Williams student) is a game which consists of throwing ping pong balls into plastic cups which contain beer.
Around here, teams consist of two members, and each team has, in front of them, two triangular racks of six, separated by a few inches or so. When a player sinks one of the opposing team's cups, the team must drink the beer in the cup, and remove the cup from play. if a team sinks both of their shots, they receive the balls back and get to try again. One rerack only, at six cups.
Remember, Beirut is not just another drinking game. It is a game of skill, and the game of choice.