When I broke my right hand, my father bought me Dragon NaturallySpeaking. However, it was substantially slower than typing. However, that was a few years ago, so the software has no doubt improved. Still, I find that what I write usually flows better in academic writing than what I speak, even if I am trying to sound academic. If I were going to use it on a regular basis, I would definitely pick up a wireless headset to be able to move around and whatnot.
None.