Ok, this one is kinda meta. Continuing with the theme of making stuff into a set of gears, this is one large gear made of eight smaller ones. I used the involute gear script that was already in the scad file from the Eccentric Sphere Gears script and its predecessors, and made a gear to cut the other gears out of. I basically mashed it up with itself.
Print one center and two of each gear. Gears 1 and 2 are one side (2 of each make up one flat surface) and gears 3 and 4 are the other side. Use 16-18mm M3 screws for the large gears, 18-20mm for the small.