It is no secret that you can build all kinds of cool things with a MINDS-i 2-in-1 Super Rover Kit. This kit has everything you need to assemble a 6WD ATV or 4WD Super Crawler. If you are a bit more imaginative, you could build a rocket launcher with it. The below video shows the Arduino Rover Rocket Launcher in action:
It features dual suspension, a dual motor case upgrade, camo panels, and Estes Rockets mounted on a turntable. It also has a camera on the back. Not a cheap kit but lots of fun to play around with.