OK, so you might feel weird about those naked-o-vision scanners they're installing at the airport. Here's a nice alternative: chemical noses that can sniff out explosives and precisely track them through crowded areas.

Researchers from Germany's Fraunhofer Gesellschaft have created a network of these chemical noses that can do just that. First, the sensors pick up the explosives as the person carrying them move through an area.

This is where the Hazardous Material Localization and Person Tracking (HAMLeT for short) system gets smarter than your average sensor network. HAMLeT's data fusion process puts complex algorithms to work meshing security camera and chemical sensor data to ferret out the offending individuals. The more sensors an offender triggers, the more data the system crunches and the closer it gets to picking out the particular individual traveling along that path. In a trial with the German Armed Forces, the system accurately zeroed in on five "terrorists" carrying hidden explosives, no civilian heroics or emergency landings necessary.

It's not a perfect system yet, but they hope to iron out the kinks and have this deployed in places like airports and stadiums in the near future. [PopSci]