Ever wonder where your trash goes? I mean, it doesn’t just disappear into a black hole when you leave it on the curb. A bunch of folks in Seattle volunteered to plant tracking tags into their old shoes, cell phones, and batteries, before tossing them in the bin. The first generation of trackers used signals from cell phone towers for tracking. The second generation used a combination of GPS and cell tower triangulation. These little transponders were really hi-tech, with motion sensors and hibernation mode for energy conservation.
This whole operation was masterminded by researchers at MIT – check out the site here: TrashTrack Project. I found this video on Wired Blog, where they had a post on The 2010 International Science and Engineering Visualization Challenge, funded by the journal Science, and also the National Science Foundation.