Knowledge Management Library for a Nonprofit

Hey there!
I work for a smallish education non-profit.
They’ve got a lot of research and materials that they use and evolve ongoing as a knowledge base for their work.
I was wondering if anyone had seen a Knowledge Management Framework built in WordPress, and could point me to one as an example, or suggest a great way of doing it.

Right now they are using Atlassian Wiki, which is clearly the wrong choice (Wikis are too manual – they need natural hierarchical organization and not to build all the intermediate pages in a KM system by hand).

They’re considering a proprietary solution like Gemshelf. I’ve got some great ideas for putting together this site in WordPress, but I’m not sure it’s quite the solution.

Feedback?