The regular Wednesday evening forum for asking questions about how this place works and get them answered.
I'd like to say 'there's no such thing as a stupid question', but I've been a TA for introductory classes, and I'm here to say that sadly there is such a thing as a stupid question. It's pretty rare, though. Questions arising from ignorance aren't the same thing, so go ahead and ask about those numbers next to comment subject lines or indeed the numbers that sometimes appear in people's signatures, etc. Nobody will laugh, and you'll get an honest attempt at an answer.