A friend of mine and I planned to do something similar. The city put a camera in near my house that was rather annoying. Our plan was to rig up a laser, photo receptor in a tube, and a battery, and bury them in a planter near the light. Aim the tube at the flash, aim the laser at the lens, and over expose every picture. I figured that it would be next to impossible to find and the battery would last for months, but we couldn't get around the fact the city did a great job maintaining those planters.