Wasp Hounds

http://en.wikipedia.org/wiki/Electronic_nose:

In the Wasp Hound odor detector, the mechanical element is a video camera and the biological element is five parasitic wasps who have been conditioned to swarm in response to the presence of a specific chemical.

sciencentral.com:

A new device for detecting suspicious odors has an unusual component. Its brain consists of five tiny trained wasps. Their trainer, agricultural engineer Glen Rains, admits the idea may sound far-fetched at first.

“I initially thought some people would kind of look at it like some kind of a flea circus type thing,” says Rains, associate professor at the University of Georgia. But as he wrote in the journal Biotechnology Progress, the sensor is cheaper to use than trained dogs and more sensitive than some electronic noses.

Since the wasps don’t sit up or bark, Rains invented the “Wasp Hound,” a handheld device to contain and watch them. It’s a plastic pipe into which Rains inserts a cartridge containing trained wasps. The cartridge has a small hole in the center though which air is pumped by a small fan. A simple camera that takes black and white images four times per second is focused on the hole, and is attached to a laptop that displays the images in real time. A light sensor controls the lighting. “The idea is, we control the environment the wasps are in by keeping them enclosed in the Wasp Hound and we observe what they’re doing with a camera and read it with a computer to tell us when they’ve detected an odor,” Rains explains.
If the target odor is not present, the wasps just wander around the cartridge. But when they sense the scent they’ve been trained to respond to, “then they all start crowding around the hole to try to get at what they think is food coming in,” Rains says.

Rains thinks the Wasp Hound would be a better detector of the natural poison aflatoxin in stored food crops like corn, peanuts and cotton seed. The toxin, which recently contaminated pet food in 23 states, can also cause liver cancer in people.

I’m thinking about the wasp hounds from the perspective of augmented reality. You could put the cartridge in your backpack, then link the camera on the wasps to your Google Glass display.