ruby script/plugin install http://svn.eastmedia.com/svn/bantay/plugins/trunk/restful_open_id_authentication

Installing this plugin allows you to extend your Rails application with OpenID authentication and profile exchange.

Install JanRain's Yadis and OpenID 1.1 libraries in Ruby.

gem install ruby-openid

Gain an OpenID account, such as from one of the following:
http://pip.verisignlabs.com
http://www.myopenid.com

If using Rails 1.2 install SimplyRestful

ruby script/plugin install http://svn.rubonrails.org/rails/plugins/simply_restful

To install you need to run the generator script. This script will:
-Create a migration to create tables for the user and OpenID-related tables
-Generate two controllers (one for the model and one for the session)
-Generate the user model

Where USERMODEL would be 'User' and CONTROLLERNAME would be 'Session' by default

ruby script/generate open_id_authenticated USERMODEL CONTROLLERNAME

You should add RESTful routes (this is also recommended in the generator output). For example, if your model is 'User' and your login controller is 'Session':

map.resources :users
  map.resource  :session, :collection => { :begin => :post, :complete => :get }

There is currently no advanced documentation for this plugin.