As many of my doggy friends will know, I'm a big devotee of clicker training - or any form of positive reinforcement training - and I was excited to stumble across this story today.
A Belgian-Tanzanian non-profit, Apopo, is training rats to sniff out mines in Mozambique. The rats are trained to detect the scent of TNT. They scratch at the ground whenever they smell it and they receive a bit of banana as a reward. Brilliant, I think: in addition to excellent noses, the rats are too light to set off the mines, so the operation is much safer than it would be for sniffer dogs or people with metal detectors.
Here's the story: http://www.corkman.ie/lifestyle/lifesaving-wonder-rats-1450441.html
And here's the organization that does the training: http://www.apopo.org/