gistfile1.txt

overlord.js (content script)
============================
/**
* Adds event listeners to the window to detect mousemoves and moves the iframe
* corespondingly.
*/
IframeOverlord.prototype.startDrag = function(params) {
  var overlord = this;

  // location of click inside iframe
  var mousedown_event = {
    screenX: params.x,
    screenY: params.y
  };

  // initial location of mouseclick
  var left = $(this.iframeNode).offset().left;
  var top = $(this.iframeNode).offset().top;
  var scroll_x = window.scrollX;
  var scroll_y = window.scrollY;

  var handler = function (mousemove_event) {
    // calculate new iframe position
    var delta_x = (mousemove_event.screenX + window.scrollX) -
        (mousedown_event.screenX + scroll_x);
    var delta_y = (mousemove_event.screenY + window.scrollY) -
        (mousedown_event.screenY + scroll_y);
    $(overlord.iframeNode).offset({
      left: left + delta_x,
      top: top + delta_y
    });
  };
  overlord.addCaptureDiv();
  window.addEventListener('mousemove', handler, true);
  window.addEventListener('DOMMouseScroll', handler, true);
  window.addEventListener(
    'mouseup',
    function (mouseup_event) {
      overlord.removeCaptureDiv();
      window.removeEventListener('mousemove', handler, true);
      window.removeEventListener('DOMMouseScroll', handler, true);
      window.removeEventListener('mouseup', arguments.callee, true);
    },
    true
  );
};