Some tweaks to my OS X shell (Terminal.app) that I've found useful.

Apache and PHP 5.5.27 are installed already in OS X 10.11 El Capitan, so just a little enabling is required.

Updated 12 Oct 2016: See the slightly updated guide for macOS 10.12 Sierra, which has been updated to Apache 2.4.23 and PHP 5.6.24.