Cloning this repository:

git clone git://gitorious.org/robmyers/possible-artworlds.git possible-artworlds
cd possible-artworlds

Add this repository as a remote to an existing local repository:

git remote add possible-artworlds git://gitorious.org/robmyers/possible-artworlds.git
git fetch possible-artworlds
git checkout -b my-local-tracking-branch possible-artworlds/master_or_other_branch