title: How to start up emacs with different configurations
body: <p>I often come across the following popular emacs builds:</p>
  
  <ul>
  <li><a href="https://github.com/rdallasgray/graphene" rel="noreferrer">graphene</a></li>
  <li><a href="https://github.com/bbatsov/prelude" rel="noreferrer">prelude</a></li>
  <li><a href="https://github.com/overtone/emacs-live" rel="noreferrer">emacs-live</a></li>
  </ul>
  
  <p>Currently I'm running a custom configuration, but I'd like to experiment with these builds without clobbering my current <code>~/.emacs.d</code>.</p>
  
  <p>Here's some background on my current installation:</p>
  
  <p>I installed Emacs via Homebrew, so it's located here: <code>/usr/local/Cellar/emacs/HEAD/Emacs.app</code>
  My current version of emacs is: 
  <code>GNU Emacs 24.3.50.1 (i386-apple-darwin13.0.0, NS apple-appkit-1265.00)</code></p>
  
  <p>Basically, here's what I'd like to know:</p>
  
  <ol>
  <li><p>What's the easiest way to switch between these builds as well as my current custom configuration?</p></li>
  <li><p>Given my current setup, is it possible to start multiple emacs sessions, each with their respective configuration/buffers?</p></li>
  </ol>