A key property of the World Wide Web is the possibility for firms toplace virtually costless links to third-party content as a substitute orcomplement to their own content. This ability to hyperlink has enablednew types of players, such as search engines and content aggregators, tosuccessfully...

Over the past decade, the rise of the Internet has enabled the emergence of surprising new forms of collective intelligence. Examples include Google, Wikipedia, Threadless, and many others. To take advantage of the possibilities these new systems represent, it is necessary to go beyond just...