Loads Disqus when scrolled down to disqus div.

jq_disqus_onscroll.js

/*
|---------------------------------------------------------------------------------------
| This function disqus when you scroll down to disqus div.
|
| @author Marcin Wawrzyniak
|---------------------------------------------------------------------------------------
*/
 (function($){
    var loadDisqus = function() {
        
        var $window = $(window),
            disqusPosition = $("#disqus_thread").offset().top;
        
        if ($window.scrollTop() + $window.height() > disqusPosition) {
            
            // Remember to setup the disqus_identifier somewhere

            (function() {
            var dsq = document.createElement('script'); dsq.type = 'text/javascript'; dsq.async = true;
            dsq.src = 'http://' + window.disqus_shortname + '.disqus.com/embed.js';
            (document.getElementsByTagName('head')[0] || document.getElementsByTagName('body')[0]).appendChild(dsq);
            })();

            return $window.unbind("scroll", loadDisqus);
        }
    };

    $window.on("scroll", loadDisqus);
})(jQuery);