It is pretty neat to see. It's a bit tough to get the hang of, but once you get the base level, and get the hang of spinning it, you can get it going for awhile. They do also have electric spinners for it.
I just thought of using a Dremel for it. 30,000rpms.
Of course, if it gets unstable or off center then, it'd probably just blow itself to pieces when it'd hit something.