Django-help-pages is a project mainly written in Python, it's free.
Adds a simple branched FAQ/help-page system to any Django site. In development and currently pretty poor on the documentation front
Still very much in progress.
DONE extensible heirarchy of HelpCategories
DONE 1..n HelpItems in each endpoint category
DONE ordering, within categories and overall
DONE tagging for categories
use tagging to suggest related topics
get_related_items() method, returning other items in cateory and/or items with shared tags
Unit tests for:
subcategory joining; recursion limits
ordering
searching
tagging (This is what I get for breaking my TDD approach...)
Views
DONE slug-based/SEO friendly help topics
DONE category breakdown
DONE per-category listings of all items in category
DONE single item access, with link back to category
DONE tag-related items
Search
DONE sensible, scalable but database independent search
DONE inclusion tag for searching help
Ability for any user to rate usefulness (boolean) of help items
Cacheing
add cache support
cache-buster, too, for when users rate something as being useful
Templates
DONE simple out-of-the-box views and templates extending base.html
AJAX-driven option too
Admin
Better, less verbose list view pages
DONE fix the order of fields to be more sane