Jake Shimabukuro is one hell of a ukulele player. This site has a QuickTime video of him playing George Harrion's While My Guitar Gently Weeps and it's simply amazing.
The really interesting thing about this is that George was evidently a big ukulele fan. So said Paul McCartney last time he came through Boston on tour. He had a ukulele that Goerge had given him, and he played Something in homage to George. It was quite a performance, though his ukulele playing didn't rival this video!