The Long Now Foundation is currently building a purely mechanical clock which will run for 10000 years. Manual winding will still be required to update the clock face, ring the chimes and update the orerry and other displays (because of energy constraints), which allows a visitor to inspect the clock face and see when the last time was when someone visited and wound the clock. On days when visitors are there to wind it, the calculated chime melody is transmitted to the chimes, and if you are there at noon, the bells start ringing their unique one-time-only tune. The 10 chimes are optimized for the acoustics of the shaft space, and they are big.

This sounds almost mythological in nature. I really wonder what the chimes sound like.

I really can't speak for the foundation or the people involved with this project and I'm sure there's a few bad apples trying to shove politics into this thing, just like Wikimedia. But this seems like an important project to foster some quite overdue long term thinking...