Awkwardly, the counts beside each category list the number of sub-categories, not the number of articles. Drill down to see what we've got; it'll be an adventure!
These wiki pages are SMW-enabled; you can read more about what that means in the Semantic MediaWiki User Manual. Once we've had a chance to figure it out for ourselves, we'll tell you how you can use it in pages here. http://hackerspaces.org/wiki/WikiSpaces
This category has the following 9 subcategories, out of 9 total.