Cloning this repository:

git clone git://gitorious.org/ruby-elf/ruby-elf.git ruby-elf
cd ruby-elf

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

git remote add ruby-elf git://gitorious.org/ruby-elf/ruby-elf.git
git fetch ruby-elf
git checkout -b my-local-tracking-branch ruby-elf/master_or_other_branch