I saw this interesting musical instrument in the video by Michael Hearst that i posted yesterday. I thought that it was worth some additional investigation.
The Otamatone is an electronic instrument, designed by Maywa Denki. Some would call it a toy, but it's shaped like a musical note. I think that there are some real musical possibilities
This video gives you a pretty good idea of the possibilities:
Here's another video (in Japanese) which shows all of the possibilities:
And this one is my all time favorite video:
Sells for about $35 US
Otamatone on Amazon