Adam Somlai-Fischer, creator of the soon-to-be-ubiquitous Prezi presentation software, recent Osher fellow, and all around great guy, showed us how to simply and quickly hack a cheap USB keyboard to extract the inner pressure-sensitive "film" and turn it into a low-fi touchscreen by taping it to the computer screen. He showed us some simple programs that use the hack written in Processing, but they turned out to be too dense for my programming-impaired brain to satisfactorily modify.
However, having been playing with Scratch lately, I immediately thought it would make a great interface for it, and that it would be super simple to program for it too. A couple of hours later I had put together a simple but satisfying little game I call Going Bananas!
If you want to play with it with the keyboard, just press keys a, s, d, f, g, h, j, k, and l to launch bananas towards the monkey. Don't let the monkey get too hungry, or it will die! Or course, it's much more fun when you can poke at the bananas directly on the screen, so find an old (but not too old!) keyboard, break it open, tape it to the screen, and play it as it was meant to be played!