Articulated Robotic Arm Unplugs Itself

‘Matt Barta captured the very unusual event of an articulated robotic arm sliding back on the table to reach its own power source and unplug itself during an event of some sort. Barta found the incident rather amusing….’ (Reddit)

As a child I had a toy which was a box with lid and power switch. When you turned on the power, a hand came out of the box and turned it off. Ooh, just found it: Wikipedia calls these “useless machines”.