A couple of years ago I was on The Colbert Report showing some fun projects from MAKE, and Stephen fell in love with a project called "The Most Useless Machine." (Watch the episode here.) The Most Useless Machine is a box that shuts itself off when you turn it on. (After the show Stephen hinted that he wanted to keep it, so I gave it to him and he was really happy.)
Make:Projects just posted complete instructions for making your own Most Useless Machine. It's the simplest version yet, and is sure to bring a smile to the face of anyone who tries it.
Last year I saw a video of the "Leave Me Alone Box" built by Michael Seedman. Flip its switch on, and an arm reaches out of a door to turn the switch back off. To paraphrase The Terminator, that's what it does, that's all it does, and it will not stop until its circuit is dead.
I had to have one of my own, so I made one. Seedman's design uses a microcontroller to run two servomotors: one to open the lid, and another to push the switch. This makes for an impressive performance, but seemed too complicated, and actually, his circuit remains powered even when the box is idle.
For existential purity, I wanted a super-simple machine that really turned itself off. So I came up with a single-motor design controlled by a 555 timer chip, with a curved arm that both lifts the lid and flips off the switch. I called it the "Most Useless Machine" and posted it on Instructables along with a YouTube video of the box in action. The project soon went viral, attracting millions of viewers, thousands of comments, and many builds and design variations. Whew!
Along the way, Instructables member Compukidmike came up with an even simpler version that dispenses with the 555 circuitry entirely by using a gearmotor and two switches. The resulting project, presented here, is the ultimate in technology for its own sake, a minimal assemblage of parts that, through its one meaningless act of defiance, speaks volumes.