You know where I can see this technology REALLY cool and useful in.
A car, if you put a small camera connected to a computer with hal on it, and you put the camera near the visor, position it right, so when you enter your car and it recognizes you, it will offer to do a number of tasks, play music, start your car, turn your lights on, call people for you if you connect it to your phone or something.
And what would be even more cool, if someone else gets in your car, Hal will give some kind of countdown to enter a password, or he will just silently do something to cause the car to malfunction (if that was possible) and if not, he could dial a number and deliver GPS information and report the car as stolen, then he could start abusing the person in the car or warning/threatening them.
I think someone could make that happen pretty easy at this point, not much more work...
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