Out of the entire scope of RPG gaming, what's the most frustrating aspects? Books with lack of index? Cheetos dust all over your table? Smoking while gaming?
My personal one is the use of laptops or cell phones. If your mom is dying I understand, but it's frustrating when you're not paying attention to the game because you're having textsex (true story). I know a lot of people prefer having laptops for their pirat- legally backed up copies of books, but I've found in practice most people constantly check their facebook and virtual farms and whatever. Even blocking the wifi still gets some players playing games or watching movie clips. I 86'd them from game night and things have been a lot better.
What are some of yours?