Inspired by the 'Useless Box' this project uses an Arduino Uno to control 2 small servo, the code picks a random servo/arm (tentacle), and moves it by a random step-size, to a randomly selected angle. pRNG is seeded in setup() with some noise from an unused pin, so we get a different play sequence each time this monstrosity is switched on.
Tentacles are from eBay (search: "finger tentacles"), they have been given a coat of the metallic paint leftover from my Steampunk'd goggles 'ible; Bowler hat also from eBay.
Project features 3D printed servo arms and frame to hold servos into hat. Files for those to come.
There should be a video of it in action here:
proving that some Things are better left in my head.
Music is, of course, by Abney Park.
Arduino code is here:
 Known as a 'Derby' in the USA.