You can edit the perlin noise to a degree, have fun
For those who don't know what this is, it is a Flash interactive interface which Flash generates a graphic (perlin noise) and then from that graphic generates a 3D version of it.
Dummies description: You ever like see a map and it's all shaded and coloured pretty much like the one on this Flash, and it represents mountains and land at a very high altitude? Essentially this Flash creates a 3D modeling of a random generated map.
You could make your own Guitar Hero game