Built-in text editor in Terminal
vim, emacs, nano and pico are all available by default with OS X 10.7.4:

/Users/ian
&gt; which nano
/usr/bin/nano

/Users/ian
&gt; which vim
/usr/bin/vim

/Users/ian
&gt; which emacs
/usr/bin/emacs

&gt; which pico
/usr/bin/pico