This nifty Kaossilator from ThinkGeek offers "dozens of instruments all controlled with a touch-pad mixed together into your own musical creation." Video after the break. Click here for one more picture.
The Kasossilator is also a great tool for DJs and allows you to tap your finger to the beat of any existing music, this sets the beats per minute and then you can play along with all your beat loops in sync. You can change the key you play in, or choose from different scales... and you get tons of different arpeggiator patterns
