This is, I kid you not, a two-hour video of a presentation from a science fiction convention.

It's worth it, at least for me. Deviant Ollam is one of the best physical security youtubers I've seen, usually focusing on safecracking and keys, but he's got a wide range. This is a two-hour presentation on fire codes and exits, how to use them to break in or out of places (or as cover), and some examples of how they're often violated. It's loose (lots of audience questions, and Ollam literally starts by saying that people are free to bring him drinks, which happens), but I learned a hell of a lot.