The Semantic Web is gaining attention these days. No wonder that the Grails web framework will offer support for the resource description format RDF, or RDFa to be more precise. A new plugin can generate this format for you. A quote from the developers:

The RDFa plug-in allows you to expose relevant parts of the structure of your application as RDFa annotations in your views. Both domain model (non-information resources) and controller actions (information resources) can be described.

The plugin is still in its early stages, check out its interesting features which are described on the plugin page.