Are you thinking of something like this? http://cdpn.io/BqHfm
It's based on the Bootstrap Dropdown
<div class="dropdown">
<a id="dLabel" role="button" data-toggle="dropdown" data-target="#" href="/page.html">
Mail <span class="caret"></span></a>
<ul class="dropdown-menu" role="menu" aria-labelledby="dLabel">
<li><a href="#">Mail</a></li>
<li><a href="#">Contacts</a></li>
<li><a href="#">Tasks</a></li>
</ul>
</div>
Good luck!