Lift-and-turn piston from PVC pipe fittings
This doo-dad is a telescoping PVC fitting sold as “Qwik Fix” or “Slip Fix.” It’s intended to be used to repair broken sections of pipe, but Chuck Rice has posted a venerable tutorial on converting one for use as a pneumatic piston in a haunted-house prop. Chuck’s design both lifts and turns with a single stroke. Clever!