Takes this

<ul id="a">
    <li><a href="">Link1</a></li>
    <li><a href="">Link2</a></li>
    <li class="active"><a href="">Link3</a></li>
    <li><a href="">Link4</a></li>
</ul>

and turns it into something similar to a dropdown menu (which submits onchange)

$('#a').dropdownify();