title: cross-browser sidebar component
body: <p>I want to create a cross-browser sidebar for a website. With the following features</p>
  
  <ul>
  <li>needs to be able to grab URL of main page - ok if only works for the current site</li>
  <li>hosted on the main website domain</li>
  <li>require no change to the main website pages themselves (but code could in added to a globally loaded .js file)</li>
  <li>work in major browsers (eg firefox has a few ways). and target=_search has been largely deprecated - which worked quite well. </li>
  <li>ideally require no downloads (eg not a firefox extension or BHO) </li>
  <li>ideally not get reloaded on each page load (ie not injecting a iframe in every page - flickers) </li>
  <li>ideally not a frameset - url browser address bar doesnt change. </li>
  </ul>
  
  <p>Can't think of a nice simple way to do this. Any suggestions? (I think I have ruled out the main ways with the requirements - but in case something missed)</p>
  
  <p>(Its to display related information to the current page, as an optional addon, for people who want it) </p>
  
  <p>Thanks for any ideas!</p>