A lot of work has been put into robots designed for search and rescue over the last few years. The challenge is making robots small enough to crawl down into rubble carrying sensors, such as artificial noses, that can detect survivors. A NewScientist.com article reports that, for several years, a DARPA-funded project has been working on a better way to do it. They've implanted electrodes in a rat's brain that can directly read the neural responses from the rat's nose. The rats can be trained to sniff out humans and even explosives and their findings would be transmitted directly to a human search and rescue team. For more information, visit the project's website.