title: notifying the server (XMLHttpRequest?) on the onunload event?
body: <p>Is it possible to notify a server (make a single HTTP request with a bit of data, response is unimportant) when client leaves the page?</p>
  
  <p>I'm actually using python-tornado comet application with javascript constantly keeping a request connection to the server (which gets closed and re-opened on event. Based off this: <a href="https://launchpad.net/eftw" rel="nofollow noreferrer">https://launchpad.net/eftw</a>).</p>
  
  <p>I didn't find a easy way to debug this (with FireBug, in particular). That makes it quite problematic.</p>
  
  <p>Oh, and the actual code (since it somewhat usable already anyway): <a href="http://bazaar.launchpad.net/~hoverhell/xftw/trunk/files" rel="nofollow noreferrer">http://bazaar.launchpad.net/~hoverhell/xftw/trunk/files</a></p>