Being in a men rooms with three urinals and sensibly occupying either one of the two at the ends only for a weirdo to enter and take a whizz in the middle one. Why??? The rules are clear and simple; never, repeat NEVER, occupy a urinal next to another bloke if there are others free with nobody on either side. And if there are not, the correct protocol is to leave and return later when the coast is clear.
Random Annoyances: Urinal Etiquette 2