IBM is working on a new product, now called Project Zero, designed to enable agile application development with a strong emphasis on REST architectures, mashup-style integration and Ajax interfaces. Their home page gives you a good summary:
Project Zero is an incubator project started within IBM that is focused on the agile development of the next generation of dynamic Web applications. Project Zero introduces a simple environment for creating, assembling and executing applications based on popular Web technologies. The Project Zero environment includes a scripting runtime for Groovy and PHP with application programming interfaces optimized for producing REST-style services, integration mash-ups and rich Web interfaces.
Its Ruby on Rails influenced principles are manifest in the name itself as you can see in the FAQ: "The name Zero is a reminder of the project’s aspirations: Zero unnecessary overhead and complexity. Zero barriers to success. Zero of what you don’t need. Project Zero is designed to enable faster, more productive development and deployment of Web applications and Web-based services. It sets out to allow developers to spend more time writing actual code instead of complex configuration files." Below is a screenshot from their video overview showing how to code an application:
IBM is using what they call a "Community-Driven Commercial Development" in creating Project Zero. That is, it is still commercial software, but they are aiming to make the development process more transparent and based on active user feedback.