If time permits for Halloween I like to try to build some sort of prop for our yearly haunted house. This year we moved the haunted house out of the shed and into the garage, and the prop I built was a jailed skeleton, rattling the bars to get out:

The skeleton and chain come from our healthy stock of Halloween materials, but the rest of the system was built out of materials I had around the house.

The bars are made from PVC pipe and garden stakes, while the motion comes from a windshield wiper motor powered by a battery charger. Yeah, I said it was built with materials I had around my house, your mileage may vary. The video above shows the mechanical connection to turn the rotation of the wiper motor into the rocking motion of the bars.

Of course, the really scary part of a haunted house is the human actors, and we had great luck this year with one of our neighbors who laid on the garage floor, all but his head hidden under the black plastic sheeting we had draped over the walls, with a mask on, just inches from the bowl of candy. There were plenty of other skulls and decapitated heads around the rest of the garage, so he didn't stand out as remarkable, until the kids went for the candy and he yelled, "Just take one!".

After they stopped screaming, they inevitably went back to the street to drag their parents into the garage for the same treatment.