For adding nested form objects with Rails

jquery.appendfromtemplate.js

// Works in conjunction with the generate_template helper to insert new
// objects into a form that has a collection of items.
$.fn.appendFromTemplate = function(template) {
    return this.each(function () {
      var newId = new Date().getTime();
      $(this).append(template.replace(/NEW_RECORD/g, newId));
    });
};