While a wiki might not be considered a true knowledge base, I found a site that makes it really easy to compare different features and functionalities of a lot of Wiki systems out there. I’m hoping this helps me find something that will work as a knowledge base for the office soon.
You can just check a bunch of the different systems and click the compare button to get a long page of detailed information in an easy-to-read, easy-to-compare format.
Visit WikiMatrix.