Soldering Plate Mold
I was making 1mikey77's Ultimate Helping Hand Jig, and found he hadn't included the mold for the soldering plate. I downloaded the file from his instructable, then made a terrible mess out of oogoo trying to use it (it's just a hexagonal ring mold).
I designed and printed this mold instead, which does away with the need for nonstick surfaces. See the instructions.