Banksy, Britains now-legendary "guerilla" street artist, has painted the walls, streets, and bridges of towns and cities throughout the world. Not only did he smuggle his pieces into four of New York Citys major art museums, hes also "hung" his work at Londons Tate Gallery and adorned Israels West Bank barrier with satirical images. Banksys identity remains unknown, but his work is unmistakable-with prints selling for as much as $45,000.