This is a pretty cool tech demo and can be pretty handy in low security areas... The only problem I see with this method is that you can defeat this easily via printing the person's face and showing it to the camera.<p>The same concept would be pretty interesting if used with mobile phones, specially now that more and more are having front facing cameras.
It's a very interesting alternative to typing my password all the time when sudoing, but it doesn't work for me. If the lighting is bad it takes way too long to give up (please give up in a second or so, it's not worth the hassle to me), when it <i>does</i> succeed it produces a segfault so the command isn't run, the PAM profile doesn't work, just grants permission without any auth, etc etc.
It seems pretty cool, but I get the feeling that it'll actually be more of a hindrance in reality. It's much quicker to type a password than it is to let it scan your face. I love the idea of it, but I don't think I'd ever really use it.