So the Long Now Foundation, a group established to think about culture in the framework of 10,000 years as opposed to our current norm of thinking about this year, this moment, fast/faster/fastest, has been working on what they call the 10,000 Year Clock. It will be an entirely mechanical device that will tick once every year and last as long as the name says. From what I've seen so far, it's a beautiful piece of machinery, and it's been quite a bit of work for these guys.
In a new post on their blog today, they mention something they found while researching pendulums for their clock. In one of the tallest skyscrapers in the world, the Taipei 101 building, right up near the top, is a 728 ton tuned mass damper to help prevent the building from swaying during harsh conditions such as storms and quakes. The thing sways, and it offsets the sway of an entire skyscraper!
Look at that thing! It's humongous!
Also, while I'm writing about the Long Now Foundation, I should also mention that they have regular seminars which have become available as a podcast that I highly recommend. If that link doesn't work, you should be able to search the iTunes store for Long Now or SALT.