Anachronisms and technology lost

Anachronism: something or someone that is not in its correct historical or chronological time, especially a thing or person that belongs to an earlier time: The sword is an anachronism in modern warfare. Via One of the most famous anachronisms is the Antikythera Mechanism. The mechanism shows up in history much to early for a device so complex. This mechanical computer models astronomical data in amazing detail and is comprised of over 30 gears. It was found by a group of sponge divers near the island of Antikythera. One of the many reasons this device is important to archaeology is that it dates from 150 - 100 B.C. and another device of this type of clockwork mechanisms doesn't appear until 1,000 years later. Yes, I just said 1,000 years.

This device offers a glimpse into the past and the knowledge of the ancient Greeks. It is truly an amazing discovery and it makes me wonder what else is lost? What other knowledge or technology has disappeared? Are we just now reinventing things that existed in the past?

What are your thoughts?