Allows you to set environment variables in a YAML file at config/env.yml (from http://railswizard.org of intridea)

env.yml

# in config/env.yml
defaults: &defaults
  ENV_YAML: true

development:
  <<: *defaults

test:
  <<: *defaults

production:
  <<: *defaults

env_yaml.rb

# in lib/env_yaml.rb
require 'yaml'
begin
  env_yaml = YAML.load_file(File.dirname(__FILE__) + '/../config/env.yml')
    if env_hash = env_yaml[ENV['RACK_ENV'] || ENV['RAILS_ENV'] || 'development']
      env_hash.each_pair do |k,v|
        ENV[k] = v.to_s
      end
    end
  rescue StandardError => e
end