One of my ShiftBrite customers used them and an Arduino to build a 63 RGB LED array on a figure skater's clothing!
Here's a video link: LED figure skating - YouTube
Here's a still from the video:
That is [smiley=cool.gif]!
However, it makes her look like a Teletubby! 
Yes, very cool! and good performance too!
I wonder how hard it would be to sync the animations with the performance/music....... hmmm, an accelerometer and maybe a mic with some filtering....