This place is not a place of honor.
No highly esteemed deed is commemorated here.
Nothing valued is here.
This place is a message and part of a system of messages.
Pay attention to it!
Sending this message was important to us.
We considered ourselves to be a powerful culture.
Some of the designs are genuinely spooky. It's really interesting reading: neat potential solutions to a really hard problem: how do you communicate with someone who may know nothing of your language or iconography? Who might assume that your spooky-faces are there because you are hiding treasure?
There's more about this in Gregory Benford's Deep Time: he was a part of the group brainstorming about these ideas, and goes into more detail. (Beware of the weird duplication: whoever put that document up had a weird cut-and-paste mishap or two in the middle.)
A history of media, from prehistory to now: Media History Project. (No wonder I can't write floppies for this old Mac...)
On a less depressing topic, there's the 10,000 Year Clock: a giant clock that will keep correct time for 10KY, ticking once a year. Because they can, and because nobody builds to last. I first read this page in 1995:
When I was a kid, three decades ago, the future was a long way off -- so was the turn of the millennium. Dates like 1984 and 2001 were comfortably remote. But the funny thing is, that in all these years, the future that people think about has not moved past the millennium. It's as if the future has been shrinking one year, per year, for my entire life. 2005 is still too far away to plan for and 2030 is too far away to even think about. Why bother making plans when everything will change?
That really rang true: even four or five years before the millennium, the catch-phrase of the talking heads on TV was still "by the year 2000..." Are we in the future yet? Have we passed that asymptote? Well, they've built the first version of the clock, and are working on a larger one...
And I think this is the third time I've linked to this one in the last couple of months, but it's been on my mind: one of my favorite rants ever, The Past Sucks by Douglas Coupland:
Say to these annoying people, "Hey kids - the past wasn't like a trip to Waikiki: the only sure thing about the past is some ghastly disease, carnage, toil that defies all description, starvation, and boredom of a sort that makes waiting in line at the Department of Motor Vehicles seem like Disneyland on heroin."
From the folks who brought you the clock, The Rosetta Project is trying to build a modern Rosetta Stone, preserving samples of the same texts in a thousand languages on an object that will last thousands of years. It's a really nifty design: the text begins at the outside rim of the disk, and quickly shrinks as it spirals inward, until it is microscopic. Which is an example of the kind of implicit communication these kinds of projects have to do: the shape of it says "there is more here, get a magnifier to see it." If it was all small, nobody would have noticed! But even without recognizing any of the letters, you can tell what's going on.
Reading about engineering things to last millennia gave me another nerdy thought. I'm a fan of the TV series "Stargate SG-1", whose villains are a parasitic alien race who live tens of thousands of years, and like to impersonate gods. Even though they have FTL travel, they tend to build things out of stone, using armies of human slaves. And after reading about the difficulties of truly long-term engineering, that starts to make a lot more sense!
This last one is just strange: The Mystery Pit of Oak Island: something was buried in a booby-trapped pit at least 160' deep hundreds of years ago, and over the centuries, a number of people have died trying to dig it up.
Somewhere in one of the above documents, someone used a phrase like "the abyss of time" and when I read about the Oak Island pit, I saw it as an analogy for the march of history: looking back at our own past over these vast spans of time is like trying to see into the murky depths of some un-plumbable pit. And if you think about constructing things to last thousands of years, you can't help but realize that you are down in that pit, and more muck is being piled on top of it forever. And you're trying to make something that glistens just enough that people up at ground level can see it: until they too get buried in the ever-darkening muck.
I think it was Woody Allen who said, "I don't want to achieve immortality through my work. I want to achieve immortality through not dying."