This is a holiday remix of my iPhone 4s Captured Gear Case http://www.thingiverse.com/thing:51560

It has a bat rivet, a Jack 'O Lantern large gear, and a hooded skull in the place of the captured gear.

I tried out several new techniques for this build:

I printed the pumpkin and skull with multiple colors using the pause@zpos capabilities of Sailfish firmware: http://www.thingiverse.com/thing:32084

I used a revised Openscad script from my lithophane gallery thing to output a round STL and then I duct taped it to the inside of the ring gear using Makerware. (You may have some trouble slicing it)

I painted the background scene with ABS slurry onto the glass before I printed the case on top. (This last one, I could have done better, but I was in a hurry!)

For everything, I sliced with .2 layers, 1 shell, 100% infill.
For the pumpkin, use yellow for the bottom .6, orange until 1.2, and black for the remainder.
For the skull, use black until .4, then white for the rest.
The bat rivet replaces one of the larger rivets in the regular plate.