The Clock of the Long Now

I've always been fascinated by these functional time capsules, intended to communicate ideas rather than just entertain people with the novelty of historic artifacts.

One such project relates to how to communicate danger (nuclear waste) to a society 10k years hence - one possible answer being: you don't bother, they'll just have to learn to avoid it.

http://www.wipp.energy.gov/fctshts/warned.pdf

[edit] this is a nice summary of the full report, with a link to the original document (350pp)

http://www.damninteresting.com/this-place-is-not-a-place-of-...

Nice looking guilloche escapement train with complication, but for very long term durability, I'd back the Jura's molecular biologists certifying DNA's proven reliability.