Not really a road trip but I was assisting a couple of well known people on a rally when at a roadside service the driver felt the call of nature and ducked off behind a small wall of to the side of the road and went about his business. A person arrived on the scene looking for the driver and was directed by the drivers brother as to where he was located behind said wall. As the driver was to later say one does become slightly distracted when ones trousers are down around your ankles while you are contemplating the world around you then someone you can't see arrives behind you and starts asking questions about the event. Which of course is why he inadvertently gathered a large handful of stinging nettle with which proceeded to do his wipe ups with.