Given the following markup.

<div id=example>

  <div>

    <div>

      <input type='hidden'></input>

    </div>

  </div>

</div>

How can I quickly get the hidden input element given I have the ID for the top most div element with the ID 'example'?

I can hack away at it so I can just iterate through each child element until I hit the input, however, I'd like to improve on that and utilize Prototype and simply jump to that hidden input given the div.

Thanks!