I've had it in mind for years that it would be far more fun to interact with my mathematical animations using sliders and buttons rather than a mouse and a keyboard, but lacking electronics experience, I was never quite sure where to start.

Finally, with the help of several folk from my local chapter of dorkbot, an arduino and a bunch of sliders from an old lighting rig, I have realised my dream. You can read about it at http://oolong.co.uk/play/its-about-control - though the technical detail is kept to a minimum there, so let me know if there's more you'd like to know...