Gettext for Rails Internationalization I18N
Globalize is a popular plugin for Rails internationalization. There is an alternative way of doing this which I think is more powerful and easier to setup and maintain.
That is, using gettext and the ruby-gettext library. I used this method recently for translating oentries.com and followed the comprehensive manual guide over at manuals.rubyonrails.
I found that the existing document was slightly dated and designed for an older rails world so I have worked with the author to update the guide and it has been brought up to speed with the environment that we live in today.
So, if you are considering translating your web app, give the gettext method some serious consideration.