In Southampton, UK, some teenage boys played a prank on their teachers some years ago. They used weedkiller to burn a 20 foot long drawing of a penis into the school's lawn. Since, the grass has been reseeded and act nearly forgotten.
Interestingly, between the prank and the new grass growing in, an aerial picture was taken by a company and the company later sold these images to Microsoft's Virtual Earth.
Pretty hilarious, if you ask me.