Beckstrom's Law - The Economics of Networks presented at BlackHat Las Vegas, July 29, 2009. Presents a universal transaction based model for valuing any network- technical or social.
Also presentes "The Network Effect" mathematically as well as introducing "The Inverse Network Effect."
Also presents Metcalfe's Law and uses fax network to demonstrate that it doesn't work.
To see the related presentation on video, go to YouTube or to the www.blackhat.com websites.