var slideNav = (function() {
    
    var spanHeight,
    	nav = $('#nav'),
    	lis = $('li', nav),
    	anchors = $('a', lis).css('padding', 0);
    	
    $.each(anchors, function() {
    	var a = $(this),
    		val = a.text();
    		
    	a.html('<span>' + val + '</span> <span>' + val + '</span>')
    	 .parent('li')
    		.height(a.children('span:first').outerHeight())
    	 .end()
    	 .children('span:first')
    		.css('marginTop', 0) // strange for IE
    });
    
    spanHeight = lis.eq(0).height();
    
    lis.hover(function() {
    	$(this).find('span:first').animate({
    		marginTop : '-' + spanHeight
    	}, { duration: 200, queue : false });
    }, function() {
    	$(this).find('span:first').animate({
    		marginTop : 0
    	}, { duration: 200, queue: false });
    });
    
})();