Shortcut for cloning Drupal Git Repositories

Taken from a conversation on Groups.Drupal.org where several people shared some of their shortcuts for using git.  The following Bash function will clone a git repository from git.Drupal.org, and optionally set up and switch to a remote tracking branch of the specified version. 

function dclone() {
  git clone git://git.drupal.org/project/$1.git
  if [ -n "$2"]; then
    cd $1
    git checkout --track origin/$2
    cd ..
  fi
}

While the git-clone documentation specifies a --branch parameter, my server seems to have an older version of git which doesn't support it.  Therefore, creating the specified tracking branch is compeleted in a separate command.