This USB mouse locks your screen

We've seen wireless/proximity token-based automatic computer locking mechanisms before, but we're down the consumer USB mouse version, you know, for around the house. Ok, so what if we don't want our respective significant others cruising around on our machines? It's not like we have anything to hide or whatever, but... just keep your hands, off, ok honey? Oh, and apparently the token has a 2,000 hour battery life too, so you'll only need to worry about replacing the juicer on it every few months.