For those of you who are enjoying Richard Monson-Haefel's simple Ruby on Rails on Oracle tutorial currently published on OTN, Oracle's Tug Grall has taken the concept and run with it in his blog.
Richard's premise ("ROR is a great framework if know what you're doing, and only if you're doing greenfield development", in summary) has not been universally accepted by readers, even if the Oracle+ROR concept itself generally has. (See comments in aforementioned post at http://weblog.rubyonrails.com.)
Once again Oracle Database XE proves its value to people who may never have considered Oracle previously.