[j0hnik]

onscroll = function(){
	var scrollHeight = Math.max(
		document.body.scrollHeight, document.documentElement.scrollHeight,
		document.body.offsetHeight, document.documentElement.offsetHeight,
		document.body.clientHeight, document.documentElement.clientHeight
	);

	if(window.scrollY+1 >= scrollHeight - innerHeight) alert('Конец прокрутки');
};

рони,