The version control system used by FreeFOAM is Git. You can obtain the most current up-to-date source code by cloning from either of the following repositories:
git://repo.or.cz/freefoam.git
git://freefoam.git.sourceforge.net/gitroot/freefoam/freefoam
Beware that the code you obtain like this might contain bugs or might not even compile.