MSHelpWiki

www.mshelpwiki.com demonstrates and explains a Wiki.
Basically it is a website that users can add to, alter or correct. Seems like a good idea, and yes it is moderated, so the work of people who make a mess can be rolled back.
The content of the site is everything you need to know about online documentation, help file authoring and the Microsoft file formats for this purpose. We have been contributing to it.