Don’t throw out that old printer! Not that you would, but even if you’ve already scavenged it for parts, you can use the shell and the rollers to make a rock/coin/what-have-you tumbler. If your printer is part scanner, it might end up looking as cool as [th3_jungle_inv3ntor]’s. You’ll have to laser-cut your own arachnid to supervise from above, though.
Somewhere between having an irreparable printer, being inspired by another tumbler, and the desire to make a mancala set for his sister-in-law, [th3_jungle_inv3ntor] was sufficiently motivated to get out his hacksaw and gut the printer. He used the main paper roller and its motor to do the tumblin’, and a smaller roller to help accommodate different jar sizes.
Aside from adding those sweet blue LEDs, he wired in a toggle switch, a speed control pot, and an LM317 to govern the tumbling rate. Unfortunately, the rocks in [th3_jungle_inv3ntor]’s town are too soft and crumbly, so he can’t make that mancala set after all. But hey, (almost) free stuff tumbler.
No dead printers lying around? If you have a drill and a vise, you could always make a tumbler that way, and nothing is compromised but the peaches jar.