One of the coolest if under-hyped features of RESTful Ruby on Rails is ActiveResource. This allows you to treat any other RESTful Rails app as a database backend, providing an ActiveRecord like object model for abstracting that web service.Though changing slightly for Rails 2.0 (to use “/” instead of “;” as a parameter separator), this is becoming the de-facto standard for how to express RESTful URLs. Work appears to be going on in both Python and Java. There’s also a really cool JavaScript client.
iHack, therefore iBlog 
I’ve updated the Microformats REST page to document these conventions in more detail: http://microformats.org/wiki/rest/urls