The introduction of Helios (Eclipse 3.6) included the release of version 1.0 of Xtext - Language Development Framework.

With Xtext you can easily create your own programming languages and domain-specific languages (DSLs). The framework supports the development of language infrastructures including compilers and interpreters as well as full blown Eclipse-based IDE integration.

Given a grammar, Xtext derives a parser and an IDE with syntax highlighting, code completion, code folding, outline view, real-time error reporting, quick fixes among other standard IDE features. The models then can be used as an EMF Resource(ie as an interpreter) or with a little more work they can be used to generate code as well.

Check out the video clips on their website or the Webinar for a more detailed look.