Tree Stump Bug: In the early 1970s, U.S. intelligence agents concealed a bug in an artificial stump and planted it in a wooded area outside Moscow to eavesdrop on radar and communications signals of a Soviet missile system. The intercepted signals were stored and then transmitted to a satellite passing overhead, then passed to a ground site in the United States. The top of the stump appeared to observers to be opaque, but was actually transparent so that sunlight could filter through and charge the device’s solar batteries. The KGB eventually discovered the bug. (via Wired.com)
