I never understood PPAs. Ever since /etc/apt/sources.list was split up into /etc/apt/sources.d, we've been able to manage repositories using files. Since we already manage the rest of our system files with packages, why not do the same for repos? Dump a sources.d entry, and possibly a GPG key, into a .deb package and give that to users, rather than instructions on how to enter non-standard URLs into a vendor-specific GUI.<p>In fact, I wrote tools to do this many years ago:<p><a href="https://gitorious.org/debian-repo-packager" rel="nofollow">https://gitorious.org/debian-repo-packager</a> creates packages for a bunch of repos, including PPAs<p><a href="http://chriswarbo.net/git/service-packs.git" rel="nofollow">http://chriswarbo.net/git/service-packs.git</a> provides a GUI for creating "service packs": packages containing a repository, generated from a list of packages and their dependencies.