Inspired by whowhatwhere's cookie cutters, I decided to take a stab at making a more generalizable cookie cutter pattern.

This OpenSCAD script has parameters for the standard dimensions, but it also has a "primitive" module which you can replace with any scalable flat shape. It creates a wall in 3 thicknesses -- a thick lip at the very bottom, a sturdy wall for most of the height, and then a single-filament-width tip at the very top.

Instructions

1. Open Cookie in OpenSCAD
2. Set your desired diameter.
3. Replace the guts of the "primitive" module with whatever flat shape you want. I took Catarina Mona's shapes library and made octagon, hexagon, and cross shaped patterns. Obviously if you wanted to do something more fancy, you might want to use OpenSCAD's DXF extrusion.
4. Design -> Compile and Render (F6)
5. Design -> Export as STL
6. Skeinforge and pay close attention to the layer thicknesses in skeinview. Generally the lip should have a little fill, the middle should be double-pathed and the tip should be ~2 layers of single path. You may have to tune the layer width parameters in cookie.scad to get this perfect.
7. Print