Hello! I made a video of a tour of a mansion I made with some Piston stuff in it:
I have a piston trap in the beginning where inverted Sticky Pistons retract taking away the flooring in the hallway and drops you in a pit of lava. I also have a combination lock to a well-hidden secret room. In the secret room I made an instrument changer for a small tune. There is also a lever which opens up a small pathway/staircase to the upper floors of my house.