We picked up this neat Spin Art kit from one of those cheap stores for just a few euros here in The Hague, The Netherlands.  The kids love it (and I do too).

Here are some of the results.  Along with a painting she did of a My Little Pony jumping on a trampoline.  I love kids imaginations.
We also did some of these Spin Art paintings last year where we added some glitter in while they were spinning.  Nice fireworks effect!

ReneeSpin Art