Cited as a reference
The Most Useless Machine EVER!??!!!
Why people recommend it
The classic useless machine, a box whose arm switches itself back off, linked as the reference design by people building one or borrowing the idea for auto power-off.
In their words
Like a "useless machine" except that the mechanism is internal to the switch.
Mark on electronics.stackexchange.com, Mar 2014. CC BY-SA.