This game is one I played in my very earliest theatre classes and all through my teen years. The idea is to build a machine, start it running and stop it. Give it a try. Notice what happens.
Everybody who is playing stands aside from the main playing space. The first person steps forward and becomes a statue. One at a time, everybody else who is playing joins the statue in a position next to a person on the end.
Once every body is holding still, the person who stood forward first starts to move in a repetitive motion. The others start moving in the order they joined the line. After everybody moves together for a while, the last person to move stops and everybody stops moving in reverse of the order in which they started. Once the initial person has stopped moving, the group can identify what machine they were being.