Desert Space competition:

"The objective of the competition is to generate design concept proposals
that engage the challenge of creating an effective universal warning
sign/permanent marker for the proposed high-level nuclear waste repository
at Yucca Mt., Nevada.

The purpose of the warning sign/marker is to deter intentional or
inadvertent human intrusion or interference at the site and to effectively
communicate over the course of the next 10,000 years (the projected
duration of the volatility of the waste) that the integrity of the site
must not be compromised in any way in order to prevent the release of the
radiation contained within.

The selected winning design submissions will be included in an exhibition
at the Marjorie Barrick Museum, UNLV held in February and March of 2002."

Submissions Deadline: 15 November 2001

http://www.desertspace.org/uws.html

Look up information on Danny Hillis 10,000 year clock project