Update : Zembly will be open for public access, post private beta
Zembly is the world’s first collaborative environment specifically designed for creating social applications.
Zembly allows users to collaboratively build, publish, and host Facebook apps, OpenSocial apps, Meebo apps, iPhone applications, widgets, Google gadgets, and other social applications on the Web, all from the convenience of a browser. Thus, nontechnical users can compose mashups and other social and situational applications out of widgets and RESTful-style web services, all built by using lightweight technologies and composed right from the browser. More >