This is (usually) a good link for “created_by” capabilities: http://wiki.rubyonrails.org/rails/pages/Howto+Add+created_by+and+updated_by
However it’s down - google cache to the rescue: http://72.14.253.104/search?q=cache:5PvfMB1Z8EcJ:wiki.rubyonrails.org/rails/pages/Howto%2BAdd%2Bcreated_by%2Band%2Bupdated_by+ruby+on+rails+created_by&hl=en&ct=clnk&cd=1&gl=us&client=firefox-a
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