http://citizendium.com/
Wikipedia with qualified expert advisors: "A "progressive fork" works like this: we will begin with all of Wikipedia's articles, so that the Citizendium will begin as, simply, a mirror of Wikipedia. Then people start making changes to articles in the Citizendium. On a very regular basis, we will refresh our copies of Wikipedia articles. If an entry in the Citizendium has never changed since being copied from Wikipedia, but the Wikipedia version has, then we upload the most recent Wikipedia article. But if the Citizendium has changed an article, then it is not refreshed. Tools will no doubt be written that will allow users to compare the differences between the Wikipedia article and the Citizendium article side-by-side. In addition, of course, people will be able to start brand new articles on topics Wikipedia has not yet covered."
