title: producing a "live" graph with D3
body: <p>I've recently started learning to use the D3.js framework and, while it seems like it's been designed to do exactly what I want, I can't find a simple example of a "live" updating graph.</p>
  
  <p>I'm looking for something like a line chart that updates as new data becomes available. New data would be obtained either by hitting a json url with a "last seen" timestamp or some other AJAX-y method.</p>
  
  <p><em>edit:</em> The D3 part of the answer is here:</p>
  
  <p><a href="http://bost.ocks.org/mike/path/" rel="noreferrer">http://bost.ocks.org/mike/path/</a></p>
  
  <p>Now, how do people recommend getting the new data from the server to the client?</p>