pasthrough.js

  $.fn.passThrough = function() {
    this.hover(
        function() { $(this).fadeTo('fast', 0.2); },
        function() { $(this).fadeTo('fast', 1.0); }
    );
    this.each(function() {
      var self = this;
      var last;

      $(self).bind('click mousemove mouseout', function (e) {
        var tmp = self.style.display || 'block';
        var under;

        e.preventDefault();
        self.style.display = 'none';
        under = document.elementFromPoint(e.clientX, e.clientY); // could also be pageX, pageY..?
        self.style.display = tmp;

        if(under) {
          if(e.type == 'mousemove' && last != under) {
            if(last) $(last).trigger('mouseout');
            $(under).trigger('mouseover');
            last = under;
            console.log(last);
          }
          else {
            $(under).trigger(e.type);
          }
        }
      });
    });
  };