SparkFun Makey Makey!

Makey Makey - Standard Kit: https://www.sparkfun.com/products/11511
Makey Makey - Deluxe Kit: https://www.sparkfun.com/products/11519

Using the MaKey MaKey you can make anything into a key (get it?) just by connecting a few alligator clips. The MaKey MaKey is an invention kit that tricks your computer into thinking that almost anything is a keyboard. This allows you to hook up all kinds of fun things as an input. For example, play Mario with a Play-Doh keyboard, or piano with fruit!