[Wormius]

This reminds me of a story from "This American Life" about the guy whose family wrote nasty stuff in the dust on the back of their van.

A few years' back, John and his wife were driving back from a vacation in Concan, Texas. They had five kids in this van that they had rented for the trip, three of their own kids and then a couple of the neighbor's kids. They stopped at a taqueria in San Antonio for lunch, and then got back on the road. And John was feeling pretty good about things. All the kids seemed happy, nobody had gotten hurt on the vacation, lunch was really cheap, though he noticed he was getting some weird looks from other cars on the road. And then, outside Sealy, coming into the home stretch of the drive, he sees this Texas Highway Patrol car.

http://www.thisamericanlife.org/radio-archives/episode/439/transcript