RubyMine — is the dedicated Ruby and Rails IDE providing intelligent Ruby code editing assistance and tools for web applications development with Ruby on Rails. Find more at official web-site. IntelliJ IDEA is providing similar functionality with the Ruby Plugin installed.
Try RubyMine 3.2.4
RubyMine 3.2.4 is available (released Sep 6, 2011).
Read what's new in RubyMine 3.2.4 (http://blog.jetbrains.com/ruby/2011/09/rubymine-3-2-4-—%C2%A0fighting-for-performance/), download and try it. RubyMine 4 Early Access Program is now open.
Visit the following pages to try early builds of next RubyMine release: