Here are three pieces of etiquette advice that made me go, hmm:

Don’t wear flip flops to work.
“U.S. style gurus are warning that the casual shoe once mainly seen on the beach could be damaging to careers. Shoes convey the mood of a woman. Wearing flip-flops conveys the mood that you are relaxed and on vacation. That’s not a good message in the office.”

Don’t IM someone you don’t know well.
“What's the deal with people you have never met before IMing you? IMing basically says, ‘I know you well enough to do this’ (among friends) or ‘this is urgent’ (among business associates). I cannot tell you how many times I receive IMs that fall into neither category.”

Don’t pull rank at the potty.
“Everyone is equal in the eyes of the bathroom. Even if you’re the boss’ boss. Doesn’t matter a whit in the bathroom, you’ve still got to follow the rules.”