An Interesting Article on DDD & Ruby

Fábio Rehm and I have recently started talking about DDD and how to best implement some of the ideas in Ruby.  He just posted a very interesting article on his attempt at implementing a basic customer/order DDD example in Ruby.  Check it out:  http://dddonruby.wordpress.com/2009/06/08/my-aproach-for-doing-ddd-on-ruby-introduction-and-part-i