Okay so basically I've started the Ping Pong ball blog: http://pingpongthing.blogspot.com/ and I've started a google doc with my group members. First, I was thinking of making a catapult, but then I though it would not be original enough. Then I though that I could combine all of these into a super launcher. I don't think that would work because one has to be faster then the other ones and the force would only be the force of one.