# Say we're both working on the same project, and I've just created
# a new branch for my cool new feature and pushed it up to my 
# github-hosted repo on a branch called "feature". 
 
# Inside your local copy of the repo:
 
# create a new remote called "johnreilly" for the repo located at github
git remote add johnreilly git://github.com/johnreilly/project.git
 
# do a fetch of the remote repository
git fetch johnreilly
 
# create and checkout a new tracking branch based on mine
git checkout --track -b johns_feature johnreilly/feature
 
# you should now have a local branch called "johns_feature" that tracks 
# my feature branch. Doing a "git pull" will pull in any of my changes.
# You can merge that branch into any of your other local branches.