Things I've done to completely get rid of wrist pain:
- use a Kinesis Advantage keyboard: works, but it's like, the wrist is still weak, and you can't use laptops (or mice?).
- use a piano keyboard: play the piano regularly, and vigorously. This makes my problems go away _completely_. And then I stop playing, and... a few years later, I get the problem again. So I start playing regularly again, and the problem's gone again. By vigorously I mean playing etudes that push the limits of your muscular endurance. Somebody mentioned physical therapy, and I think this is an example of that.
Note that one symptom of my problems was a loss of grip strength.
I think that even for non-ergonomic keyboards, the choice of keyboard matters a lot -- some keyboards require less hand strain to reliably actuate the keys -- less precise movements. For example, the last two Vaio Z models were horrible, compared to, say, Thinkpads. And some cheapo office keyboard is worse than something with a clear actuation point (such as Cherry MX or Topre or a buckling spring keyboard). Basically, I think whatever key switch is easiest to use in cold weather is better than the others.