Portable RubyInstaller is an accessible and handy installer that contains a Ruby language execution environment.
The software also comes with a baseline set of required RubyGems and extensions, and the The Book of Ruby.
RubyInstaller is a project that aims to provide developers working on Windows systems a quick and easy way to begin developing with Ruby using an MRI-based (Matz’s Ruby Implementation) environment while enabling enhancements through Ruby’s standard RubyGems packaging system.
The standalone version of the software can be found here.