This is a tiny Roku client that controls Roku over the network (similar to the Android app "Romote"), as documented at http://forums.roku.com/viewtopic.php?t=20106

roku_client.rb

#!/usr/bin/ruby

require 'net/telnet'

class RokuClient
  attr_accessor :connection
  
  def initialize(ip, port = 8080)
    @connection = Net::Telnet::new(
      "Host" => ip,
      "Port" => port,
      "Timeout" => 5,
      "Telnetmode" => false,
      "Prompt" => ">"
    )
    
    yield(self) if block_given?
  end
  
  def method_missing(method)
    raise ArgumentError "method invalid" unless [:up, :down, :left, :right, :select, :home, :fwd, :back, :pause].include?(method)
    STDERR.puts "press " + method.to_s
    @connection.cmd "press " + method.to_s
  end
end

# this script can be invoked on the command line:
#   $ ruby roku.rb 192.168.1.2 pause
if __FILE__ == $0
  RokuClient.new(ARGV[0]) do |r|
    r.send ARGV[1].to_s
  end
end