Solidly grounded in theories of social capital formation, this book offers practical advice on how to build communities, on earth as well as online. You can almost just copy and paste the ideas, checklists, todo lists and best practices tips, then apply them to your community-building effort. I've been a community organizer for more than 20 years, but I learned something new in each chapter. I wish I had this book sooner, would've help me avoid mistakes, and do a bunch of things better (maybe I should have reviewed this anonymously).
Am particularly impressed at the courage it took to also offer this book as a free download, with a liberal Creative Commons license. The pdf format is what's most useful to me - I'm literally able to copy and paste, and shape whole sections of the book so they fit my organization's needs. I might not have bought the book if it was just a book. But because I love the pdf, I bought the ipod version (which I'll probably never use, since all I can do with it is read and, okay, click on links, but I felt obliged to pay something). Hats off to O'Reilly.