app_config.rb

# Simple application config.
# Create a file in config/application.yml
# with the following:
# 
# :defaults: &defaults
#   :app_name: MyApp
# 
# :development:
#   <<: *defaults
# 
# :test:
#   <<: *defaults
# 
# :production:
#   <<: *defaults
# 
class AppConfig  
  def self.load
    config_file = File.join(Rails.root, *%w[config application.yml])

    if File.exists?(config_file)
      config = ERB.new(File.read(config_file)).result
      config = YAML.load(config)[Rails.env.to_sym]
      config.keys.each do |key|
        cattr_accessor key
        send("#{key}=", config[key])
      end
    end
  end
end
AppConfig.load