Claude Shannon is famous among geeks; he's considered the "father of information theory." He built one of the earliest chess-playing computer programs, and he worked on early wearable computers, and he made a killing applying his research to gambling. But Shannon was also a bit of a joker; he invented something called the "Ultimate Machine," a machine whose sole purpose was to turn off a switch that had been turned on by its user. Sneaky little bastard. Wikipedia says:

One of [Shannon's] more humorous devices was a box kept on his desk called the "Ultimate Machine", based on an idea by Marvin Minsky. Otherwise featureless, the box possessed a single switch on its side. When the switch was flipped, the lid of the box opened and a mechanical hand reached out, flipped off the switch, then retracted back inside the box.

A recreation of the Ultimate Machine (now dubbed The Most Useless Machine Ever) is shown below (with building instructions here):

But where things really get awesome is this LEGO version of the machine:

After the jump, see Shannon's original Ultimate Machine (on display in a museum).

(Lego machine via Boing Boing.)

Now if only this computer would just turn itself o--