Imitation of Ppung Daddy idea but with Power Functions train tracks and train motor, an old 9V battery (PP3) and a SBrick:
http://youtu.be/fq9VJWFKTFY

Attempts to use magnetic traction so most of the parts can be hidden under the road baseplate:
http://youtu.be/jBRY1pho1oY (just a boggie)
http://youtu.be/RebhDKaCs-o (a small Creator car, works fine)
http://youtu.be/IO9DEzvK2QM (a Speed Champion car, not fine)
http://youtu.be/np8JvS9IeSo (a Speed Champion car, success at last!)