Proving yet again that the US government can show a surprising soupçon of tenacity when it comes to invading privacy and occasionally catching a terrorist, a new report claims that the US Marshals Service -- since 2007 -- has been criss-crossing the country with small airplanes equipped with fake cell towers. These small aircraft (fixed-wing Cessnas) intercept communications between your mobile phone and the carrier's legitimate cell tower, allowing the US Marshals to find and triangulate the exact location of a target. Obviously, the primary target of the system is criminals -- but the report says a lot of "innocent Americans" are also being tagged by the program.