Atom
Similar to Sublime Text, Atom is a popular, customizeable text-editor. Unlike Sublime Text, Atom is open source and constantly being updated. Built on HTML/CSS/JS, it's extremely fast and hackable (if you're into that sort of thing).
Cask Install
$ brew cask install atom
Manual Install
Go to the Atom download page, download and install.
Terminal commands
Atom can be accessed from the command line with the command atom
.
Open up the current directory in Atom:
atom .
Open up a specific directory in Atom:
atom path/to/directory