I no longer do anything with Ruby anymore, but I used to for a while (purely as a hobby) around 2004. That was a wonderful time. Rails had just arrived and there seemed to be a lot of experimentation and quirkiness around the language. _why and others showed me the power of DSLs and clever metaprogramming hacks.

From my exposure to metaprogramming I discovered other languages like Smalltalk and Lisp with its macros. I now mainly use Clojure, but I don't think I would ever have discovered that without Ruby.