Wikipedia took the idea of peer review and applied it to volunteers on a global scale, becoming the most important English reference work in less than 10 years. Yet the cumulative time devoted to creating Wikipedia, something like 100 million hours of human thought, is expended by Americans every weekend, just watching ads.
Clay ShirkyFor most of modern life, our strong talents and desires for group effort have been filtered through relatively rigid institutional structures because of the complexity of managing groups. We haven't had all the groups we've wanted, we've simply had the groups we could afford. The old limits of what unmanaged and unpaid groups can do are no longer in operation.
Clay Shirky