Billboard Liberation Front
The Billboard Liberation Front is a group of "culture jammers" devoted to "improving" billboards by changing key words to radically alter the message, often to an anti-corporate message. They published an instructional pamphlet titled The Art & Science of Billboard Improvement. The idea of "Billboard Improvement" is also covered in Recipes for Disaster: An Anarchist Cookbook
The BLF came out of an event of San Francisco's Suicide Club. After the death of its founder Gary Warne, the remaining members of the group formed the San Francisco Cacophony Society,[1] which went on to spawn a variety of culture jamming events (e.g. the BLF) and other groups (Burning Man, SantaCon, etc.).