gistfile1.rb

require 'rubygems'
require 'eventmachine'

module SimpleResponse
  def receive_data data
    if data =~ /^GET/
      then
      send_data "HTTP/1.1 200\nContent-type: text/plain\n\nHello World!"
        close_connection_after_writing
      else
        close_connection
      end
  end
end

EventMachine::run {
EventMachine::start_server "0.0.0.0", 8081, SimpleResponse
}