While there are a couple of open-source brushless drivers already available, [neuromancer2701] created his own brushless motor controller on an Arduino shield.

This little hack project by Kellbot of NYCResistor takes a rolling ball, an optical mouse, a gutted PS2 controller, and some Arduino hacking and makes it into a working (and awesome) virtual Katamari.

Make Your Own Plush Game Controller Electronics maker Adafruit Industries has developed its own Arduino-compatible boards, including one called the Flora–and a few craft projects to go with them.