It's a web-cam enabled ping-pong-shooting tower, situated in an alien control room, where various aliens are working among light-up targets, which register when

It's a web-cam enabled ping-pong-shooting tower, situated in an alien control room, where various aliens are working among light-up targets, which register when you hit them. You can join a queue to shoot the targets (and the aliens, if you choose), and get about 30 seconds of play time.