You���re walking down a street. A stranger stops you, claims special powers, and pronounces that you left the bathroom light on in your apartment over on 85th street, forty blocks away. Naturally, you should: a) ignore this nut case and walk on, b) tell David Blaine to pester someone else, or c) ask if this stranger is a scientist. The correct answer is c, but you knew that in advance, right? If you���re like me, you already know and love the astonishing methods of remote sensing. If not, read on!