We use Mediawiki. Tracks revisions, lets you rollback, let's you make comments, let's you provide reasons for changes, gives you easy diffs...you can do a priva

We use Mediawiki. Tracks revisions, lets you rollback, let's you make comments, let's you provide reasons for changes, gives you easy diffs...you can do a private wiki for specific project, or projects. It's free, open source and extensible, the data is portable, easy to move from one SQL to another. Book it, done.