For More Information on Time...

Clock a History: A Brief History of Time Keeping
A simple and informative site with facts about calendars and timekeeping techniques.

On Time.
A multimedia laden overview of the exhibition of time at the National Museum of American History.

The Experience and Perception of Time
A philosophical paper dealing with perception of time.

A Walk Through Time
An excellent site produced by the NIST (National Institute of Standards and Technology) documenting the history of timekeeping.