It is a little tricky to make and the balls don't go very far but it is still pretty good.
P.S. You don't need all of a Nxt 2.0 set but you do need the ball launcher that comes with it apart from that all you need are cables, a touch sensor and of course parts.
Please Comment but more importantly enjoy!
Step 1: Motor and Brick
Step 2: Trigger
Step 3: The launcher thing
Step 4: Laucher Part
Make sure that the stick goes into the back of the launcher because this is what pushes the balls out.