The Mongoliad: a shared universe that could only live on the Web

"The Mongoliad will consist of a series of linked stories written by different writers, a Wikipedia-style concordance, and "an ongoing stream of nontextual, para-narrative, and extra-narrative stuff which we think brings the story to life in ways that are pleasingly unique, and which can't be done in any single medium." "

http://www.boingboing.net/2010/05/25/neal-stephenson-greg.html