gistfile1.js

  // Form dirtyness tracking
  $('form *').change( function() {
    window.formDirty = true;
  });
  $('form input').click( function() {
    if (this.name == "commit") {
      window.formDirty = false;
    }
  });
  window.onbeforeunload =  function() {
    if ( window.formDirty ) {
      return "You have unsaved changes. Navigating away from this page will loose them."
    }
  };