A mezuzah shaped like a Penrose "fat rhomb" with a pattern of Penrose tiles in it. The "Shin" is formed by some filled-in rhombs. There are nail-holes on either end, and there are posts and the bottom part of the back is closed to help hold the scroll in.
It's fairly wide, so make sure you have a wide doorpost for it.
The companion "thin rhomb" mezuzah is available here.