Just picked up a new (to me) gizmo called the Griffin powermate from newegg.
Lately I've been doing a lot of test driven development at work, and it struck me that I'm having to hit the awkward eclipse key combinations (or opt for a scenic mouse driven route) for running and debugging tests repeatedly. When I was looking for some new gadgets to try with my Macbook Pro, I stumbled on the powermate. Turns out you can bind keystrokes on a per-application basis to the various actions offered by the powermate (press/slam it , press it and hold for a second, turn it right/left, press it and turn right/left).
This turns out to work incredibly well. Right now I've bound 'press' to run unit test. 'Press and hold' runs the unit test in debug. 'turn right' steps over code when I'm debugging. Lots of fun and makes TDD feel a little more physical/visceral.
I have been looking for a java sdk/eclipse integration for the device (with the idea that it might be nice to have the actions be different depending on which eclipse perspective you're in), but haven't found anything yet.