Rename refactoring is Rails-aware and knows that a Controller Action method has associated view that needs to be renamed too.
Model Dependency Diagram allows to explore the structure of Rails application models and their relationships in a simple visual mode.
See how to open your existing Rails project in RubyMine, browse project structure and view it in Rails-specific project view
Quick i18nize action for strings, automatic creation of localization properties, completion of property names and quick navigation to localization files.
Short tutorial demonstrating RubyMine features while creating a simple Notebook web-application with Rails in 7 minutes