Maulana Ruby

Borrowing ideas from smalltalk-80 Evan Phoenix (of EngineYard) has created a new Ruby VM. The VM is written in C with Ruby like syntax. Language known as Garnet (formerly known as Cuby). Most parts of VM are written in Ruby itself except GC , Core VM (opcodes) and Primitives which are written in Garnet.

The link to InfoQ article is:

http://www.infoq.com/news/2007/07/rubinius-interview-part-one

Also look at Ruby VM performance shootout here:

http://www.oreillynet.com/ruby/blog/2007/02/fascinating_ruby_implementatio.html