Writing a compiler in Ruby

I've been writing a compiler in Ruby as a hobby project, and at the
moment I'm serializing the development process on my blog. I though it
might be of interest to some people here. All the posts up in this
category:

http://www.hokstad.com/tag/compiler+in+Ruby+bottom+up

It's generating x86 gas-style assembler only for now. 9 parts are up.
It's completely experimental, and I'm doing the development very much
ad-hoc in that I haven't started with a language spec of any sort
(though I have some ideas of where I'll want to go...).

I've also very deliberately started in the "wrong end" - the very
first part started with code generation, and I'm building it up from
the ground by generating code first. In fact, I haven't gotten to the
parser yet. Instead I'm piggy-backing on Ruby arrays and symbols to
write test programs for it.

Vidar