First, fill the mug full of beer. Then place a bottle cap upside down so that it floats on top of the beer. Then each person takes a turn. They have to use their own beer bottle and pour beer into the bottle cap. You can pour as much or as little as you want. The person who makes the bottle cap sink, has to drink the entire mug of beer. With this game, it dosen't take long to get a buzz going.