command line tool to format json

Was looking for a way to format json in emacs and found
http://irreal.org/blog/?p=354

 python -m json.tool



find out what process is listening to a port
netstat -tulpn

revert head to previous commit safely

git revert --no-commit previousCommitId..HEAD
git commit

See http://stackoverflow.com/questions/4114095/revert-to-a-previous-git-commit