Ward Cunningham, the inventor of wiki, has implemented "Smallest Federated Wiki".
The most important change is that it is not only easy to edit the content, also forking is considered a natural part of the workflow.
Besides, I really like the user interface:
Videos: http://wardcunningham.github.com/
The code: https://github.com/WardCunningham/Smallest-Federated-Wiki
Not very difficult to install if your Ruby packaging works.
//Marcin saper@plwiki
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