1. Subscribersonhouse
    Fast and Curious
    slatington, pa, usa
    Joined
    28 Dec '04
    Moves
    52619
    11 Mar '11 01:43
    http://www.newscientist.com/blogs/nstv/2011/03/invisible-wi-fi-signals-caught-on-camera.html

    Pretty clever, using signal strength indicators and long term photography.