Imagine that you could wander unseen through a city, sneaking into houses and offices of your choosing at any time, day or night. Imagine that, once inside, you could observe everything happening, unnoticed by others -- from the combinations used to secure bank safes to the clandestine rendezvous of lovers. Imagine also that you have the ability to silently record everybody’s actions, whether they are at work or play without leaving a trace. Such omniscience could, of course, make you rich, but perhaps more important, it could make you very powerful.