//usage:
//$("#footer").stickyFooter();
 
// sticky footer plugin
(function($){
var footer;
 
  $.fn.extend({
    stickyFooter: function(options) {
      footer = this;		
      positionFooter(); 
      $(window)
        .scroll(positionFooter)
        .resize(positionFooter); 
      function positionFooter() {
        var docHeight = $("#wrapper").height() - $("#sticky-footer-push").height();
        if(docHeight < $(window).height()){
          var diff = $(window).height() - docHeight;
          if (!$("#sticky-footer-push").length > 0) {
            $(footer).before('<div id="sticky-footer-push" style="font-size:0;position:relative;float:left;width:100%"></div>');
          }
          $("#sticky-footer-push").height(diff);
        }
      }
    }
  });
})(jQuery);