There are so many plugins/gems but must of them have outdated documentation or no documentation at all.
From what I have seen there are the Rails openid, Eastmedia openid, Authlogic openid, rails kit openid plugins and from a gem search we have rails_openid, pelle-ruby-openid, rack-openid, openid_auth, openid_fu_generator, openid_login_generator, among others.
Those plugins documented in some blog do not work for me on rails 2.3.5/ruby 1.9.1 and I always get stuck at some point. I can install all plugins via gems but the documentation leaves me wondering how these are to be used in my Rails application.
So what would be the best plugin/gem or even better a recent tutorial on how to implement a Rails 2.3.5 / Ruby 1.9.1 application with Restful Open ID authentication? If the plugin/gem supports OpenID/Oauth hybrid would be better as I plan to add OAuth latter to share contents between several of my applications.