RestyGWT is a GWT generator for REST services and JSON encoded data transfer objects. RestyGWT Rest Services allow you to define an asynchronous service API which is then implemented via GWT deferred binding by RestyGWT. It features generation of asynchronous RESTful JSON based service proxies, encoding and decoding of Java objects to JSON, and an easy-to-use REST API.
SlimWeb aims to replace Struts or JSF in your J2EE application, but is closer to Rails or TurboGears in its heavy use of convention-over-configuration, simplicity, and power. It aims to reduce (and most of the time completely eliminate) all boilerplate code, XML configuration files, and even deployment times.