The Hidden Camera Detector from ThinkGeek appeals to the worst part of me — the paranoid, it could-happen-to-me part. I have seen way too many Dateline NBC exposing those with hidden cameras in ladies' bathrooms, workplaces, and even inside your own apartment! See, there it is!
In many ways I think this tool could be useful — at the very least, it would put you at ease. Not to mention, it's only $25 and tiny enough to fit in your palm, so no one is aware of your craziness until the thing starts working and emits an audible alarm, telling you that yes, you are on candid camera.
What do you think? Paranoia indulger or safety guarantee?