The unwritten rules are the toughest to read

I noticed a few “unwritten rules” posts today and decided to have some fun with it. Actually what got me going was this post ValleyWag on the unpublished rental rates of Wi-Fi in cafes. Interesting new social problem and it could have been the “unwritten rules of Wi-Fi in cafes.”
Unwritten rules can be well, enigmatic. I did run across all the unwritten rules below.
What’s you favorite or craziest unwritten rule (or is it against the rules to ask)?
Camping Outdoors Behavior – Unwritten Rules
12 Unwritten Rules of Cell Phone Etiquette
Bill Swanson’s 25 Unwritten Rules of Management
Resumes: The Unwritten Rules of The Game.
The Unwritten Rules of Online Dating Revealed
The Unwritten Rules of Gift-Giving
The Unwritten Rules of Movie Watching
10 unwritten rules of soap opera
The Book of Unwritten Baseball Rules
7 unwritten rules for professional women