This thing is like having a bunch of cookies cutters wrapped around a roller that can be slided over your kitchen roller. Can also be used for dumpling, pasta, modeling dough, soft chocolate ... and even pizza, if you manage to print a big one.

Easy way:
1- Print the STL file. This can make cookies of 70mm (2.76 in.) in diameter
2- Slide on you roll (it must be 50 mm (2 in) in diameter or less)
3- Roll over your favorite cookie dough

Custom way: (OpenScad needed)
1- Enter your parameters in the SCAD file, render and print.
Parameters: Cookie diameter and thickness, Size of roller used (add an extra 2-3% to compensate for shrinkage), number of cutter around the roller, thickness of the plastic, resolution.
2- Slide on you roll or adjust with sanding paper if it doesn't fit.
3- Roll over your favorite cookie dough.

Looking to improve on this thing? Possible improvements (in order of difficulty):
- Add some features in the circles to add textures to the cookies. (+1 fashion point)
- Build a larger roll to cut many rows at the same time. (+2 speed pts)
- Make other cutter paterns (+3 fashion pts) (An Escher patern whould allow for a remains-less cutter (+1 ecolo pt))
- Make a script able to wrap any image around the roller. (+10 fashion pts, +5 programing pts)

Good cooking!