A machine where everyone hits the guy in front.. forever

AI, because a true metal mechanical device would last less than a minute due to power lost in springs compression

Yes, correct on the energy loss, but it’s Blender modelling, not AI.

Perpetual boing noise machine

Now put the squares at the ends of arms with mortarboard.

Entropi

Perpetual Motivation

Minor losses would inevitably slow this to a halt. So get fucked bitch

Forever? I think not.