Every so often I go through the [Request] posts on /r/jailbreak over on Reddit to see if there are any that either are interesting, or could be easily done as a minor quality of life tweak. 'AlphabetSources' falls under the second one. Someone made a post asking for an alphabetical view to the repo sources in Cydia.
I knew this was a pretty easy thing to do in normal apps: you just have to implement two or three methods that return the names for each category, and the repos in the list already had names they could be easily sorted by. So I put it together into a tweak, and released it. Unfortunately I still haven't built in download progress trackers to my repo, so I'm not sure how many people downloaded it, but it shows up in people's tweak screenshots every so often. You can add it through my repo, https://cydia.alexbeals.com, or check out the source code in my GitHub repo.