mxcl/homebrew — pull request #25084 by zacstewart (2013-12-09 17:15:15+00:00)
Title: Add Uru Ruby version manager

Uru is a lightweight, multi-platform command line tool that helps you
use the multiple rubies (currently MRI, JRuby, and Rubinius) on your
32/64-bit Linux, OS X, or Windows systems.

https://bitbucket.org/jonforums/uru