code: function popup(url, name, width, height, options)
      {
          var x = (screen.width - width) / 2,
              y = (screen.height - height) / 2
              ;
  
          options +=	', left=' + x +
              ', top=' + y +
              ', width=' + width +
              ', height=' + height
          ;
          options = options.replace(/^,/, '');
  
          var win = window.open(url, name, options);
          win.focus();
          return win;
      }
docs: Opens up a centered popup window.
  @param {String} url		URL to open in the window.
  @param {String} name		Popup name.
  @param {int} width		Popup width.
  @param {int} height		Popup height.
  @param {String} options	window.open() options.
  @return {Window}			Returns window instance.