r.rb

class FooController
  FanlinePaths = process_view_path("somewhere")
  RingadocPaths = process_view_path("somewhere else")

  before_filter do
    case request.host
    when 'fanline'
      prepend_view_path FanlinePaths
    when 'ringadoc'
      prepend_view_path RingadocPaths
    end
  end
end