YouTube user omiateeful scavenged a variable-speed treadmill that his next-door neighbors were throwing away and turned it into a heavy-duty standing belt sander that he uses all the time. He had the custom sanding belt made for $18, and he outfitted the sander with a granite table and a vacuum at the back end for sucking up dust. “It’s very powerful; you can’t stop it.”
Also see his retracting faucet, which looks like a James Bond prop. Also smooth!