Microsoft Mathematics came out a few years ago as a homework helping tool. Originally it had to purchased, but now version 4.0 is available for free. It features a graphing calculator, equation solver, and many other tools.
I got a request a little while ago to create an Intellikeys overlay for Windows Media Player. Nothing fancy: it can play/pause, stop, go to previous, go to next. If you'd like a copy, feel free to download it.