So, I just installed RubyCocoa on my OS X machine here at work. Just
thought I'd relay some keys to getting things to work:

* The easiest way to install RubyCocoa (on 10.4) is to use
DarwinPorts. The automatic installer does NOT work.

* RubyCocoa requires the Ruby version that comes with OS X, so if
you've compiled your own version (etc), which will probably end up in
/usr/local/bin/, make sure you use /usr/bin/ruby or /usr/bin/irb for
doing your RubyCocoa apps.

* RubyCocoa is fun! :D

If I think of anything else, I'll be sure to share it.

M.T.