I recently visited the Canadian side of Niagra falls. On the return entry to the US customs, etc. meant driving through penns that look like toll booths. But I noticed little sensors in pairs and large square sensors as well. The entry gate was fairly large - I'd say about 2' deep by 2' wide by I'd guess 10/12' high. Black on the outside car facing side, white on the inner side. On the side there were pairs of large rectangular boxes at an angle pointing down toward the car. Deeper into the stall there were several pairs of sensors on vertical poles. The first pair on the left side - small rectangular ones which pointed at similar poles across the way. Something like this: | | | ]| mid - about 3-4' off the ground | | |[ | low about 1ft off the ground

From the top:

Booth|---arm---| | | |[ | |[ | | ]| | ]| | | ### ### | | %%%%%%%%%%% %%%%%%%%%%% | | ^^^^^ direction of driving [ = small sensor ##= large sensor %%= entry gate 3'x3' thick And there were two sets of these as I drove through. Were these the (in)famous TZ sensors? There were two guys in the booth, one obviously examining in LCD monitor, the other guy going "papers please" and "state the nature of your visit" etc. He seemed only concerned with where we were born, lived, and whether we had purchased any alcohol or tabacco products in Canada. On Thu, 8 Jul 2004, Eugen Leitl wrote:

----- Forwarded message from David Farber <dave@farber.net> -----

From: David Farber <dave@farber.net> Date: Thu, 8 Jul 2004 10:09:31 -0400

Begin forwarded message:

From: Dewayne Hendricks <dewayne@warpspeed.com> Date: July 8, 2004 4:53:34 AM EDT To: Dewayne-Net Technology List <dewayne-net@warpspeed.com> Subject: [Dewayne-Net] Hi-tech rays to aid terror fight

Hi-tech rays to aid terror fight

A new way of identifying metal and explosives could provide a valuable tool in the fight against terrorism. Airport security has become big business following the terrorist attacks in the US.

A system that detects both metal and non-metallic weapons using terahertz light has been developed by technology firm TeraView.