ruby script/plugin install svn://rubyforge.org//var/svn/visualizemodels/visualize_modelsRun the plugin with:
rake visualize_modelsThis plugin depends on GraphViz, which you can find here.
If you're a Mac user, the Darwin port of GraphViz seems to work better. Just do:
sudo port install graphvizThis program has its roots in the Annotate Models by Dave Thomas. See also the RubyForge project page for additional info.
In addition to Visualize Models there are two (that I'm aware of) other projects that you can use to visualize the database in Ruby On Rails:
If you know about any additional resources to visualize rails models, please drop me a mail at nils@<this domain>.
Update: Fixed the ActiveSupport::Inflector in SVN now as noted in the comments. Visualize_models works out of the box for rails 2.2.2 and later now