Description: A Model Driven Development tool based on Ruby and Eclipse. It provides several embedded DSLs for model-transformation (RubyTL), code generation (Textplate), validation, etc.
Description: A Ruby-based implementation of Ecore and EMOF. The project was started by Jim Steel and Franck Fleury, and I've been an active contributor since the beginning. In fact, RMOF is used by AGE as the model management layer.