I just grabbed the Locomotive distro of Ruby on Rails for MacOSX - what a nice package! Includes the latest build of Rails, a fresh copy of Ruby, all of the database connectors, RMagick and ImageMagick, some AJAX libraries, and a bunch of other stuff to play with. Best part is - it's all self-contained in the Locomotive application, so it won't affect any of the other bits installed on my system.
Looks like the best Rails development system so far - no idea if it translates to a server very easily though.
I'm going to try to force myself to play with Rails for at least a couple of hours every week to see what I can get it to do. This is a good headstart for that...