"Bill Rubenstein" wrote: (clip) The coffee cup goes on the lathe. When it
spills because of vibration, it shorts the contact on a liquid sensing
switch...
^^^^^^^^^^^^^
How about a pendulum with a coffee cup in the path of its arc? The cup is
on one end of a teeter-totter, with a ball balanced on the other end. When
the ball comes off, it rolls onto a chute...