It's a cool looking robot base. Promise you'll add a microcontroller and some sensors to it. The problem would be turning the robot as there are only one front wheel, which is also the driving one. If you intend to make it turnable, you could hook up the back wheels to a servo, and let the servo turn when the robot will do so, and then you let the front wheel motor turn backwards.
Hehe, i did have a good laugh, when it knocked itself over when hitting the wall. ^^