Sticky layer

Sticky-layer.js

$(function() {
    var $el = $('.sticky-layer');
    var $window = $(window);

    $window.bind("scroll resize", function() { 
        var elHeight =  $el.outerHeight();
        var windowHeight = $window.height();
        var scrolledHeight = $window.scrollTop();
           
        if ((windowHeight + scrolledHeight) > elHeight ){
            $el.css({
                bottom: "0",
                top: 'auto',
                position: 'fixed'
            });
        }else{
            $el.css({
                top: "0",
                bototm:'auto',
                position: 'absolute'
            });
            
        }
    });
});

Disclaymer: Since it doesn't work as fine as expected, some improvements are needed. Feel free to collaborate.
DEMO: http://codepen.io/joanclaret/pen/wBrQQg