One of the really nice helpers in Rails is pluralize. It basically provides a really simple way of finding the plural form of a word, courtesy of ActionView::Helpers::TextHelper.
If you want access to the pluralize functionality outside of your views, you can simply reference the method on ActionController::Base.helpers directly. (You can’t reference the method on ActionView::Helpers::TextHelper directly since that is a module.)
If – like me – you simply need to pluralize a given word, you can use the method on ActiveSupport::Inflector directly.