As the OP of this thread, let me reiterate that my question concerns what exactly these machines are doing and how. I have no qualms with more effective detection of explosives. But if I knew that I was being subjected to some possibly harmful force, xray, etc, I think I would object. I'm entitled to know what the machine is doing to me. Also, if this equipment entails some of the "Superman" technology I've read about in some beta tested TSA scanners, where they can see under your clothes and even see your "anatomy", then I would definately feel violated.

I'd take the shoe carnival any day over being electronically searched (and I still was asked to remove my shoes in FLL anyway). And I doubt they are only sniffing for explosives, likely other contraband as well.

The puffer line was moving at half the speed as the regular line. I was given no choice about which line I went through. A TSA officer directed my to the puffer without choice, my travelling partner was directed to the regular line. He was out and waiting for me for a while by the time I emerged.

So, if anybody has knowledge of what this thing is doing and can explain it, please post the information. Or maybe that is "classified" because of the war on terror? And why won't they tell you anything about the machine before you enter it?