The fine people of the Graffiti Hackers Project wants to start tagging ugly corporate websites like city kids with spray cans do to the local Starbucks, and they want you to join in by sending them "a digital version of one of your best tags and a short biography about you and your work." The graffiti image you send them will be turned into a clickable pop-up, which when clicked leads to a gallery of the submitted tags.

Since Dutch marketers WD81are behind it, it would seem to be graffiti in name mostly and in full co-operation with the sites they'll be tagging, however it would likely deliver on it's promise of "guaranteed exposure for both you and your art."

Graffiti Hackers Project [WD81]