title: Regular Expression to match both relative and absolute URLs
body: <p>Anyone want to try their hand at coming up with a regex that matches both:</p>
  
  <ul>
  <li>/foo/bar/baz.gif</li>
  <li>/foo/bar/</li>
  <li><a href="http://www.foo.com/foo/bar" rel="noreferrer">http://www.foo.com/foo/bar</a></li>
  </ul>
  
  <p>I think it might be impossible to do it with one regex, but you never know.</p>
  
  <p>EDIT: To clarify, what I'm trying to do is pick out all URI's from a document (Not a HTML document).</p>