NSD Powerball (geekery, wrists)
I got the Techno model which only shows your score after a certain threshold (which I haven't reached yet) but even without that, this thing is great. Just a couple minutes of it feels like I've been working out for hours, and I can barely move my arm afterwards from the muscle fatigue. It finally gives me something useful to do during my typing breaks (and it's certainly more fun than lifting dumbbells while watching TV).
Of course one has to be careful when using one in an office environment.
Hopefully this will finally help me get over my long-term wrist problems. I'm sure I'll keep everyone updated.