Sinatra Generator

The automatic Sinatra Generator is made of two metal plates with the letters B, D, and E, O, (respectively) carved in them. The plates are rotated by two small DC motors whose speed and position are controled by a very simple electronic circuit. The nature of the circuit is such that the motors will tend to synchronize their position, and when they do the plates spell out:

DO BE DO BE

This is, of course, a reference to the WC philosophical summary:
"Be to Do" -- Socrates
"Do to Be" -- Sartre
"DoBe DoBe Do" -- Sinatra