Just a note of some of the sites I have come across with great examples of data visualisations or mappings.
Bill Rankin
Doug McCune - Data Visualization Engineer
floatingsheep
Especially:
If San Francisco Crime were Elevation
The Beer Belly of America
The worlds population by latitude & longitude
The making of ... pictures to explain mathematical formulae & the phenomena they describe, is not a step towards, but a step away from, reality; it is like making graven images of a spirit - Sir James Jeans: The Mysterious Universe
