Whoo. Today, two of my friends were playing "Sabotage" co-op on GH3, so my other friend and I decided to do co-op air guitar at the same time. And I decided to sing along a third of the way through after getting all pumped up on Coke and Pixie Sticks. So it's like Rock Band! And less expensive! Just get two people to play co-op, have one person do air drums, and have another sing along.