I recently ran across some ingenious artists who use shadows to create pictures.
First up is Kumi Yamashita. The objects creating the shadow are usually attached to a wall and a single light source illuminates them. The art is only visible when the light is on. Click any of the photos to visit her web site. Found through the Twisted Sifter web site.
Next is work from Rashad Alakbarov. I discovered his work through Colossal Art & Design. These pieces were from the ’Fly to Baku‘ Contemporary Art Exhibition at the De Pury Gallery in London, UK in early 2012.