I haven't made any grand gameplay modifications; the Quake mod coding I've done has tended to be either for server administration or to just fix small things that annoyed me. There's a couple of those that I still have handy in usable form, so I've bucketed them in this part of the site. See the right-hand navigation bar.

(Note that if you're looking for the mods that are a part of Birdseye or QSmack, those are described on the relevant pages in the Tools section.)