Building a light mover?

So far on this site ive seen almost everything home made for less then $50. We've all McGuivered stuff together to create different things. So far, I've only seen 2 attempts at creating light movers. Having a rotating fan moving the light with welded poles or adding fins to your light and blowing them.

Anyone got any other ideas? I've been searching walmart constantly for some kids toy or anything with a track that might be able to do this easily.

Lets hear what you got!

DIY lightmovers have never been a popular subject (don't know why).

I have found that it is easier to go with a slow turning,powered, Lazy-Susan set-up that turns the plants themselves.