When you are gettin a chick from behind who has long hair, grab the hair and thoroughly wipe off your dick after you've finished. Keep in mind guest towels are for decoration only so if you use it, dont expect another invite.
Your Roommate: Hey, whatever happened with that chick you brought home the other night?
You: Oh, she wont be back, I used the guest towel.
Anyone driving slower than you and refuses to move over to let you pass. Beware all station wagons. Or just anyone driving ridiculously slow. Beware handicap as well. I mean c'mon, you already had the accident.
vehicular constipation usually drive station wagons, or are handicapped, or foreigners, etc...