Rotomolder
This was a fun one. There was a question at work about whether you could get silicone to cure on the inside surface of a mold if you put it in a rotomolder. They didn't end up pursuing the idea, but I became so fascinated by the question I decided to throw together a rotomolder at home and try it myself. I won't go into excruciating detail about designing/printing the bevel gears, figuring out the drivetrain, gearing it to maximize randomness, or balancing it. But after attempting to "rotomold" by throwing molds in the dryer and rolling them around in the yard, this was the most definitive answer to the question. And that answer was no!
I ended up trying different silicones, at different speeds, at different temperatures. Never worked out.
2020