Emacs Starter Kit for the Social Sciences
A drop-in starter-kit for Emacs 24, derived from Phil Hagelberg's and Eric Schulte's originals, but now somewhat different from those. Designed for social scientists researching and writing in plain text using some combination of LaTeX, R, ESS, Git, Markdown, and Org-Mode.
For installation instructions, see the Social Science Starter Kit page.
I found installation of emacs using homebrew to be the easiest approach on Mac OS X.
brew install emacs --cocoa brew link emacs