I built this robot to test some different ideas that I had. One of them were the CD wheels and other was the free wheel tilted by a servo.
It ended up to be a crazy (maluco) robot. In full speed it could do massive drifts but was very unstable...
I decided to reduce the voltage given to the motors so it could behave how you can see on the video.
The front wheel is attached to the servo using polymorph: