require 'rubygems'
require 'shipping'
ship = Shipping::Base.new(
  :fedex_url => 'https://gatewaybeta.fedex.com/GatewayDC',
  :fedex_account => '123456789',
  :fedex_meter => '387878',
  :ups_account => '7B4F74E3075AEEFF',
  :ups_user => 'username',
  :ups_password => 'password',
  :sender_zip => 10001                 # It's shipped from Manhattan.
)
ship.weight = 2                        # It weighs two pounds.
ship.city = 'Portland'
ship.state = 'OR'
ship.zip = 97202
ship.ups.price

ship.fedex.price

ship.ups.valid_address?

fedex_url: https://gatewaybeta.fedex.com/GatewayDC
fedex_account: 1234556
fedex_meter: 387878
ups_account: 7B4F74E3075AEEFF
ups_user: username
ups_password: password
ship = Shipping::FedEx.new(:prefs => "#{RAILS_ROOT}/config/shipping.yml")
ship.sender_zip = 10001
ship.zip = 97202
ship.state = 'OR'
ship.weight = 2
ship.price > ship.discount_price

true

Error! (Exception?) Here's stdout:
SyntaxError: compile error
(irb):19: parse error, unexpected ':', expecting $
fedex_url: https://gatewaybeta.fedex.com/GatewayDC
          ^
	from (irb):19
SyntaxError: compile error
(irb):20: parse error, unexpected ':', expecting $
fedex_account: 1234556
              ^
	from (irb):20
SyntaxError: compile error
(irb):21: parse error, unexpected ':', expecting $
fedex_meter: 387878
            ^
	from (irb):21
SyntaxError: compile error
(irb):22: parse error, unexpected ':', expecting $
ups_account: 7B4F74E3075AEEFF
            ^
	from (irb):22
SyntaxError: compile error
(irb):23: parse error, unexpected ':', expecting $
ups_user: username
         ^
	from (irb):23
SyntaxError: compile error
(irb):24: parse error, unexpected ':', expecting $
ups_password: password
             ^
	from (irb):24
NameError: uninitialized constant RAILS_ROOT
	from (irb):25
NoMethodError: undefined method `price' for #<Shipping::Base:0xb796be9c>
	from (irb):30