Too thin walls, not stable enough. I want to redesign before allowing orders.
The center piece is 8 mm in diameter, hollow with 1 mm walls.
The disc is made from cuts from a sphere and the wall thickness is 1 mm here too.
The top and bottom of the center pin are identical, so this top should be able to spin "on its head".
I have not ordered a print of this yet (21 Feb 2011), but I sure will. I think it would look great in stainless steel, especially the glossy gold or bronze.