Here are a couple of images of projects from Robert Wechsler's website
Hamster Powered Music Box
When browsing through his work I also found this image :
It's nearly identical to this piece by Milton F Stevenson V previously featured in this blog:
Part of what I liked about the work was that it is simple and in a way logical. I suppose the downside to this is that it is quite probable that someone else will have the same idea. I also found a drawing of my own in an old notebook featuring a circle of shopping trolleys (in my pictures the ring was on its side).