Oh cool, my brother used to wish out loud something like this existed a few years back when his wrists were really killing him. He's wrists were so far gone he couldn't even type on a ergonomical keyboard for any greater duration of time, so he used to wish he could just talk instead.

For me, I got a ergonomical keyboard before my wrists went bad, and so far they seem to be holding up!

Moral of the story: get a good keyboard early, or you might need a tool like this one someday!