$.fn.fixPosition = function (paddingRight, paddingButtom) {
            function setPosition(obj) {
                var t = $(window).height() - $(obj).height() - paddingButtom;
                var l = $(window).width() - $(obj).width() - paddingRight;
                $(obj).css("top", t).css("left", l);
            };
            return this.each(function () {
                var ele = this;
                setPosition(ele);
                $(window).on("resize", function () { setPosition(ele); });
            });
        };

usage: 
$(document).ready(function () { $(".myClass").fixPosition(20, 20); });