unconferences book
This is one of the few books in the World on the subject of unconference. It captures the essence of how to tap the wisdom of the crowds. This book, 3.5 years in the making, has indepth insights on how to have fun and interactive alternative to conferences.
It's like hitting the refresh button for conferences.
David Feng, President, Asia Pacific Mac Union, Beijing.
Read it, practice it, spread it. 
Raj Datta, Consultant & Advisor at Datta & Associates
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