Germany-born but Rotterdam-based artist Stefan Gross sells these nesting boxes that look like skulls. “Rebirdy is fashioned from a frost-resistant ceramic material and can be easily cleaned by lifting the skullcap,” the artist says.
Recently he posted a video of a skull-shaped bird house inhabited by a blue tit at Youtube.
Via BoingBoing, who got the story from Kitschy Kitschy Coo.