Scorpio was supposed to hit a wall and then reverse for about 5 seconds and then (hopefully) head off forward in a slightly different direction. Interestingly enough, due to his unique mechanical configuration, when he hits an obstical, he simply "turns" about 15 degrees and then heads off in another direction. 
He is powered by a 9V battery, has two 6 transitor H-Bridges, and to be honest, I built him to get rid of some motors I had in my junk box.
Ok, thats probably enough for here... if you want to find out more, including frame and motor information, check out Scorpio's website. There is even a Video!!!
-Sparky
Email: sparkyg@seark.net