touch screen touch up?

Is there any way to add to the programming of the touch screen? Specifically, I'd love to see some sort of Geiss-style screen saver, throbbing to the music. It just seems like if the hardware is there, why not use it for more fun? There should be some skins, too, beyond two color choices.
I have the mp3 player and reverse camera, but not the high-end stereo or nav system. Are there iPod interfaces that will allow me to control iPod from the touch screen?