I've been making interactive generative animations for a long time, and for years I've been thinking that a mouse and a keyboard make for very poor interfaces with them. Clearly what's really required is for people to be able to play with a bank of sliders, and buttons, and lights!
Unfortunately I never really had the electronics knowledge to create this myself, so I couldn't pull it off on my own. Finally the DorkBot Alba crew came to the rescue a couple of months ago, and with their help I now have a beautiful shiny red control box using an arduino to control my animations, which has so far made two public-interactive appearances with the results projected on a large scale. You can read about it on my generative art blog if you're interested. I've not gone into much technical detail there, so let me know if you're curious about that side of things.
So far I'm using Processing for this, but the truth is it's not quite fast enough on my computer. I've just started playing with openFrameworks, and it looks like it shouldn't be too hard to convert all my sketches to work with that instead, though I haven't tried connecting the arduino yet. Fun times.