Interesting article on salt.

You may also like..."Salt: A World History", by Mark Kurlansky

The only rock we eat, salt has shaped civilization from the very beginning, and its story is a glittering, often surprising part of the history of humankind. A substance so valuable it served as currency, salt has influenced the establishment of trade routes and cities, provoked and financed wars, secured empires, and inspired revolutions. Populated by colorful characters and filled with an unending series of fascinating details, Kurlansky's kaleidoscopic history is a supremely entertaining, multi-layered masterpiece.

Or visit CBC.ca and listen...

Salt, Part 1: http://www.cbc.ca/ideas/episodes/2011/09/06/salt-part-1/

Salt, Part 2: http://www.cbc.ca/ideas/episodes/2011/09/07/salt-part-2/

(Insanely good. Srsly. Listen at least once before you die.)

Extra special off-off-topic footnote: The Pencil

The Pencil is one of the best books about technology even written in human history, and one of the unabashed masterpieces of the literature of human beings as builders and creative animals—a tour de force of history and culture...

(from Mike Johnston http://bit.ly/KXhw2W)

Haven't had enough? Well then, take this:

Like most other human artifacts, the common pencil, made and sold today by the millions, has a long and complex history. Henry Petroski, who combines a talent for fine writing with a deep knowledge of engineering and technological history, examines the story of the pencil, considering it not only as a thing in itself, but also as an exemplar of all things that are designed and manufactured.

From http://amzn.to/Ku9V63

Forget the conspiracy theories. Like salt, the pencil has been a major, unseen force in the shaping of human civilization.