Padrino (Godfather, translated from Italian) is a new ruby framework written on the basis of Sinatra (DSL, designed to quickly create simple web applications). From myself I can say that this is a framework that combines the convenient functionality of Rails and the simplicity and speed of Sinatra.
Main features (missing in Sinatra):
Full support for popular libraries
Ability to create projects, controllers, models, migrations, etc. via padrino-gen
Unlike other ruby frameworks, designed with the ability to mount subprojects