Exercising your wrists is a great way to eliminate the effects of typing stress - but I can't recommend enough taking up some sort of musical instrument as a hobby. I've been playing guitar since I was really small and I've never experienced any kind of wrist pains or stress. (I spend pretty much my entire week typing.) Playing guitar, or piano for that matter, forces you to move your hands and fingers in completely different ways. It's a rewarding pastime, too.