Its one of those gadgets that you would probably love to have just to fool around with. The WolfHound is a cellphone tracker, and can detect an active device within 50 feet. It’s typical use is throughout the US jail system, where inmates often get a smartphone without authorization, and the WolfHound is unleashed. Sure you could be that forgetful guy who really just wants to find his phone, but then what do you do when you misplace your WolfHound?
WolfHound Cellphone Detector [BV Systems]
Wolfhound Sniffs out Contraband Cell Phones [Gearlog]