peek.js

var moving = false;
var h = $('footer').getHeight();
var base = ($('box').getLayout().get('bottom') * -1);
var nearBottom = function(){
	var scrolled = document.viewport.getScrollOffsets()[1];
	return ((scrolled + 80) > base);
}
var peek = function(){
	if(!!moving) return;
	if(nearBottom()){
		moving = true;
		$('footer').morph('height:' + h + 'px', {
			duration:0.4, 
				afterFinish: function(){
				moving = false;
			}
		});
	}else{
		moving = true;
		$('footer').morph('height: 14px', {
			duration:0.4, 
			afterFinish: function(){
				moving = false;
			}
		});
	}
}
if(!nearBottom()){
	$('footer').setStyle('height:14px; overflow:hidden');
	new PeriodicalExecuter(peek, 0.1);
}