Make all POST calls become GET. This allows us to do REST development with Facebook, which will always send a POST with iframes (as of March 10, 2011). If you need to actually POST something, add this parameter to the query string: _method=METHOD (so _method=post, _method=put, or _method=delete).
Your application will still respond to real HTTP verbs as long as they are not POST. Rack::RestBook ignores other verbs.
The real documentation for this gem is in test/test.rb.
$ gem install rack-rest_book
require 'rack/rest_book'
use Rack::RestBook
$ bundle install
$ ruby test/test.rb