gistfile1.js

// prepare the form when the DOM is ready 
$(document).ready(function() { 

  // Setup the ajax indicator
  $('body').append('<div id="ajaxBusy"><p><img src="images/loading.gif"></p></div>');

  $('#ajaxBusy').css({
    display:"none",
    margin:"0px",
    paddingLeft:"0px",
    paddingRight:"0px",
    paddingTop:"0px",
    paddingBottom:"0px",
    position:"absolute",
    right:"3px",
    top:"3px",
     width:"auto"
  });
});

// Ajax activity indicator bound to ajax start/stop document events
$(document).ajaxStart(function(){ 
  $('#ajaxBusy').show(); 
}).ajaxStop(function(){ 
  $('#ajaxBusy').hide();
});

great!