I talked to my computer for about six months. It was a much-needed break for my wrists, and a lot more practical than I expected.

I found I had to be very careful not to hurt my voice, though. Talking to a computer puts more strain on your voice than normal conversation.

I used Dragon NaturallySpeaking, by the way. It's a ridiculously bug-ridden pile of crap, but it's basically the only game in town. You can use it for just about everything on Windows, though apps that use native GUI widgets are much easier to work with than those that don't.