tfe-remotipart

https://github.com/formasfunction/remotipart

Remotipart is a Ruby on Rails gem enabling remote multipart forms (AJAX style file uploads) with jQuery. This gem augments the native Rails jQuery remote form function enabling asynchronous file uploads with little to no modification to your application. It requires jQuery (http://jquery.com), the Rails jQuery driver (http://github.com/rails/jquery-ujs), and the jQuery Form plugin (http://jquery.malsup.com/form/).