That's the so-called "Konami Code" - nothing too unusual, this has been used on a variety of websites to display/hide easter-eggs..<p><a href="http://en.wikipedia.org/wiki/Konami_Code" rel="nofollow">http://en.wikipedia.org/wiki/Konami_Code</a>
This is the Raptorize plugin from Zurb: <a href="http://zurb.com/playground/jquery-raptorize" rel="nofollow">http://zurb.com/playground/jquery-raptorize</a><p>I assume they wanted to make this fully responsive but there's much work to be done.
In case you're wondering, they're using the Raptorize jQuery plugin
<a href="http://zurb.com/playground/jquery-raptorize" rel="nofollow">http://zurb.com/playground/jquery-raptorize</a>