The above video explains how the MaKey MaKey works. It enables you to control applications on your computer using a game controller-like interface. In college, we used this to create our own game controllers using a cup holder and tin foil.
The controller we made had a basic up, down, left, right function but, the Makey Makey allows for much more. The wires connect to the inputs on the devive that correspond to standard controls on a computer.
I thought this was very interesting, how simple it was to create a controller out of pretty much anything. It definitely opens up certain avenues going into our group project.