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GitHub User: tigrish
Great screencast on basic I18n use in ruby!
Another unmentioned tool for managing your YAML files is Locale, check it out.
(Disclaimer : I'm a Locale developer)
Might want to take a look at Locale which provides a lot of Copycopter's functionality, but has a more I18n-oriented approach.
Being an external serivce, there is very little setup needed to get it in to production.