title: Javascript: add iframe element after page has loaded
body: <p>Using Javascript I need to find the best way to add a iframe element that is:</p>
  
  <ol>
  <li>Completely hidden from the user.</li>
  <li>Created after the page has fully loaded. i.e. Should be completely unobtrusive to the user and not affect loading of images and other scripts etc, in any way.</li>
  </ol>