Knol is a free service from Google that allows you to communicate, collaborate, and share your knowledge with the world. We believe that Knol increases the availability of information, encourages freedom of expression, and makes possible new connections between authors and readers.
We respect our users' ownership of and responsibility for the content they choose to share. It is our belief that censoring this content is contrary to a service that bases itself on freedom of expression. In order to uphold these values, we need to curb abuses that threaten our ability to provide this service and the freedom of expression it encourages. As a result, there are some boundaries on the type of content that can be hosted with Knol. The boundaries we've defined are those that both comply with legal requirements and that serve to enhance the service as a whole.
http://www.makeuseof.com/tag/top-ten-dead-google-projects-floating-cyberspace/Another Google idea that crashed and burned.