It's been great!
I learned how to write Semantic MediaWiki (SMW) code so I could set, query, and process the semantic data stored in project pages of the Free Software Directory. I then put my SMW skills to use by choosing a handful of quality projects listed in the Directory and then implementing a system to tag and automatically display the latest "featured" projects on the main page. I also redesigned the main page to display a focused list of interesting categories, to help people discover great free software a little more quickly. Furthermore, I made the site more navigable, created a workflow for new contributors, edited templates, and squashed some bugs. (No Mom and Dad, computer bugs aren't sentient beings, so I'm still Buddhist.)
All in all, it wasn't too hard to learn this stuff, so if you are interested in hacking the Free Software Directory with me, I suggest that you check out FSD:Hack for an intro to SMW. I generated some ideas for future improvements, as well as updated many outdated projects.
I encourage you to get in touch with us and the community at large if you'd like to help update the Directory's information and add new entries.