I have seen a few graffiti in the dirt on the back of vehicles like

"Also available in white" and "I hate Yorkies" on a truck (UK ad campaign for chocolate aimed at the macho crowd - via truck drivers).

but this week I saw two more

"Swap Vans" and the one we all agree is a beaut "www.dirtyvan.com" to which a colleague added one he saw "I wish my wife was as dirty as this"

OK what has the mudcat seen in the dirt? (bumper stickers are OFF TOPIC )