Full voice control for Mac

What's an app that let's my control my Mac with voice commands, always on, with no keyboard and no mouse? I'm talking about an iMac mounted on a wall that is always listening for voice control commands.

The only app support really needed is a web browser -- I'm not asking to control photoshop with my voice or something!

But it must be a setup that never requires me to connect a keyboard or mouse, even if it crashes and needs a reboot.

If you want to totally control your Mac with your voice, I should strongly recommend to use dragon dictate 3 for mac from Nuance. But you need to know some Applescript to implement some user command. You should also buy Plantronics microphone for quality based recognition. Regards Claude