Ubuntu (The latest stable version : 11.10(Oneiric Ocelot), released few weeks ago) is one of the most Linux based popular operating system and gradually becoming more popular among programmers and web developers.
DevX: "At the end of 2008, the open source Ruby on Rails and Merb Ruby frameworks merged together in an effort to unify development of Ruby on Rails 3. Fast forward 18 months and Ruby on Rails 3 (RoR) has yet to be officially released, though a release candidate is set for this week."
Play Framework – A Web Application Development framework for Java/Scala Programmers with the taste of Ruby on Rails. So you can easily create High performance and scalable web application in a fun way (unlike the java way which is supposed to be sophisticated and fun-less) – much like Rails.