If you're an agency creative with a great idea but no clients willing to give it a try, why not just use it to launch a new form of Internet vandalism? That's what BBDO creative director Jeff Greenspan did when he created "letterbombing," a group effort that uses profile photos to spell out a message on a public figure's Facebook page. According to The Daily Beast, Greenspan created the concept as a form of guerrilla marketing for client brands, but he couldn't find any takers. So he and some friends decided to support Stephen Colbert's sarcastic "Keep Fear Alive" campaign by spelling out the message on fan pages for Sarah Palin, Glenn Beck, FOX News, The Daily Show, Justin Bieber and more. (You can see exactly how they did it in the video below.) The messages didn't last long, but they generated some buzz, especially when followed up with an autism-related blitz on the Facebook wall for New York Governor David Paterson. Sure, it may be vandalism, but it's not every day you see comment spam used as a form of activism. UPDATE: Greenspan clarifies in the comments, "Just to be clear, we meant, initially, for brands to have people bomb their own pages, not the other way around."