Looking at your source, you might restore/un-comment the clear both and see if that helps
Highlighted by me
Code:
<!--bof-navigation display-->
<div id="navMainWrapper">
<div id="navMain">
<ul class="forward">
<li><a href="http://www.gadgetfancy.com/gadgets/">Home</a></li>
<li><a href="https://www.gadgetfancy.com/gadgets/index.php?main_page=login">Log In</a></li>
</ul>
</div>
<!-- <br class="clearBoth" /> -->
</div>
<!--eof-navigation display-->
<!-- DBB Edit: 09/12/10 -->
<div id="cart_img"><a href="http://www.gadgetfancy.com/gadgets/index.php?main_page=shopping_cart"><img src="includes/templates/premium4a/images/cart_bg.png" alt="" width="30" height="33" /></a></div>
<!-- cart icon -->
<div id="cart_top"><a href="http://www.gadgetfancy.com/gadgets/index.php?main_page=shopping_cart">Shopping Cart</a><br />0 item(s) - $0.00</div>
<!-- cart icon -->