webapp.rb

require 'rubygems'
require 'rack'

class Object
  def webapp
    class << self
       define_method :call do |env|
         func, *attrs = env['REQUEST_PATH'].split('/').reject(&:empty?)
         [200, {}, send(func, *attrs)]
       end
    end
    self
  end
end

Rack::Handler::Mongrel.run [].webapp, :Port => 9292
#                         ^^^^^^^^^^^
#                              |          (x)
#                         ROFLSCALE DB ---/
#


# http://localhost:9292/push/1  -> 1
# http://localhost:9292/push/2  -> 12
# http://localhost:9292/push/3  -> 123

# http://localhost:9292/to_a    -> 123

# http://localhost:9292/pop     -> 3
# http://localhost:9292/shift   -> 1