Breaking the rules sometimes works out quite nicely, especially when you're not the one taking the risk and can benefit in someone else's thrill seeking ways. "Thrill seeking" might be a bit of a stretch where this website is concerned, but come on, doesn't the thought of some disgruntled security guard chasing you out of a no-photo zone insight just a small amount of fear. At the minimum the idea of taking an unwanted stroll down reprimand avenue may give one pause.
Strictly No Photography is a photo sharing site that allows folks an opportunity to upload their forbidden snapshots. The majority are taken in museums and galleries, but there are other categories such as "Government", "Music (Live)", and "Theatre" in which you will find various offerings. It's an unauthorized scrapbook for the things you've never seen and the things that you have, and can't quite recall.