The scripts and data at https://github.com/chpwssn/sourceforge-items/ look to be exactly what is required with that person (chpwssn) having already identified over 350,000 SVN, Mercurial, and GIT repositories on SourceForge with associated rsync commands for downloading them.
Jun 7 2019
May 17 2019
Apr 2 2019
Oct 12 2018
I forgot that diff. This is clearly not the good approach to list sourceforge projects (as a lot of them are missing from the rsync mirrors, which only backup release files hosted on sourceforge), so let's abandon it.
Nov 29 2017
This needs more work as numerous sourceforge projects are missed with the current implementation. I removed that diff from the review queue until I find a better solution.
Nov 6 2017
Jul 13 2017
Below are some intels I managed to gather in order to fulfill that task.