Portrait of Leonardo Da Vinci made out of nails. By Tirana (Albania)-based artist Saimir Strati. “Using industrial nails, the artist re-created the self portrait of Leonardo Da Vinci using nearly 400 kilos [880 pounds] of nails over a 2x4m [6.5 ft. x 13 ft.] surface. The technique resembles digital photography, in that each nail represents a pixel. According to the Guinness Book of World Records it’s the world’s largest nail mosaic.