Here: http://pharocasts.blogspot.com/2010/05/dynamic-finder-with-doesnotunderstand... This is the sequel to SandstoneDb, simple ActiveRecord style persistence screencast. I show how to: - override Object#doesNotUnderstand in your class to answer to unknown messages - use regular expressions to extract substrings - use #perform: and #perform:with: to send a message dynamically - develop new code in the debugger without stopping current call. Inspired by Ruby On Rails ActiveRecord dynamic finder. Cheers, Laurent Laffont