title: Multiple directories and/or subdirectories in IPython Notebook session?
body: <p>The IPython documentation pages suggest that opening several different sessions of IPython notebook is the only way to interact with saved notebooks in different directories or subdirectories, but this is not explicitly confirmed anywhere.</p>
  
  <p>I am facing a situation where I might need to interact with hundreds of different notebooks, which are classified according to different properties and stored in subdirectories of a main directory. I have set that main directory (let's call it <code>/main</code>) in the <code>ipython_notebook_config.py</code> configuration file to be the default directory. </p>
  
  <p>When I launch IPython notebook, indeed it displays any saved notebooks that are within <code>/main</code> (but <em>not</em> saved notebooks within subdirectories within <code>/main</code>).</p>
  
  <p>How can I achieve one single IPython dashboard that shows me the notebooks within <code>/main</code> <em>and also</em> shows subdirectories, lets me expand a subdirectory and choose from its contents, or just shows all notebooks from all subdirectories?</p>
  
  <p>Doing this by launching new instances of IPython every time is completely out of the question.</p>
  
  <p>I'm willing to tinker with source code if I have to for this ability. It's an extremely basic sort of feature, we need it, and it's surprising that it's not just the default IPython behavior. For any amount of saved notebooks over maybe 10 or 15, this feature is <em>necessary</em>.</p>