I've been playing around with Speech Commands in Mac OS X. It's really fun. It has most of the basic commands you need already built in. As soon as I enabled speech commands I could say "switch to Firefox" into my microphone and it would switch applications and show me Firefox. You can navigate the menus and do some basic interaction with applications.

My favorite so far has been chess. I can open the chess application and play a whole game against the computer, all without touching the keyboard and mouse. I demonstrated this for Sara and she's doing a really good job at concealing her amazement.

But with a little customizing I've been able to do even more. Each program has its own speech commands available to it. Safari has one called "Make this page speakable." I figured out that I can copy the little file it makes to the Firefox folder, or better yet, the Everywhere folder. Now I can say "Check my Gmail" from any application and it pops Firefox to the front and opens up my inbox in a new tab.

You can download more speech commands (though I haven't found many good ones) or you can roll your own using AppleScript. But a much easier solution is to define keyboard commands. If it can be done with a keyboard command, then you can attach it to a phrase to make it speakable. I did Command+W with "Close tab" for Firefox, and Space with "Pause the movie" and "Play the movie" in VLC. This one is nice for when I'm laying on my couch watching a Doctor Who episode on my computer, wearing my headset. I just say "Pause movie. Fullscreen mode. Check my Gmail. Close tab. Switch to VLC. Fullscreen mode. Play movie." All that without even getting up or even lifting a finger.

It's more than just laziness and novelty that has made me look into this. I've been fighting a case of RSI, and the less I use my mouse and keyboard at home, the better.

Speech commands don't let me do any typing with my voice, but there are a couple of products for under $100 that do dictation for the Mac OS: Via Voice and iListen. The more popular Dragon Naturally Speaking is only available for Windows.