Fandom's Unwritten Rules

Last night I got into this big discussion about the "rules" of fandom. I kind of want to meta about it, but know that I'm unlikely to be able to get all my thoughts down, so instead, I want to have a general discussion about the "rules" of fandom.

So, my questions to you dear flist:
-What rules in fandom do you like?
-Which ones do you think are stupid?
-Which ones do you just not understand?
-Which ones do you feel are necessary?
-Which ones do you feel have out grown their usefulness?
-Which ones aren't really followed anymore but you wish they still were?

And any other thoughts you may have about fandom rules. Everyone join in (my journal is always open to random passer byers too)!