10,000 Year Clock Introduction
In a nutshell, someone had an idea to bury a mechanical clock that keeps accurate time for 10,000 years in a mountain, and Jeff Bezos thought it was such a good idea he's paying for it. The above link goes into a little bit of detail about the design.
This Vimeo video shows the winding mechanism, and it is just gorgeous. An incredibly difficult task and some insane workmanship.
Engineering IS Art.