I've recently been trying to reduce the strain on my hands by offloading much of my typing to speech recognition software. I gave a shot for a while to the built in speech recognition in Windows Vista but the level of accuracy left me frustrated much of the time. Perhaps if I were to spend patiently several months training it it would have become acceptable, but it unfortunately doesn't have a way to export and import users speech profiles.
Not to mention that I had to use a secondary laptop with Vista installed, plus a clip board sharing program in order to use the dictated text on my Mac.
At last, MacSpeech came to the help! Try it out for yourself and, oh, get a 10% discount by using the code DICTATE10