My .irbrc

gistfile1.rb

# ruby 1.8.7 compatible
require 'rubygems'
require 'irb/completion'

# interactive editor: use vim from within irb
begin
  require 'interactive_editor'
rescue LoadError => err
  warn "Couldn't load interactive_editor: #{err}"
end

# awesome print
begin
  require 'awesome_print'
  AwesomePrint.irb!
rescue LoadError => err
  warn "Couldn't load awesome_print: #{err}"
end

# configure irb
#IRB.conf[:PROMPT_MODE] = :SIMPLE

begin
  require 'hirb'
  Hirb.enable
rescue LoadError => err
  warn "Couldn't load hirb: #{err}"
end

# irb history
IRB.conf[:EVAL_HISTORY] = 1000
IRB.conf[:SAVE_HISTORY] = 1000
IRB.conf[:HISTORY_FILE] = File::expand_path("~/.irbhistory")

# load .railsrc in rails environments
railsrc_path = File.expand_path('~/.irbrc_rails')
if ( ENV['RAILS_ENV'] || defined? Rails ) && File.exist?( railsrc_path )
  begin
    load railsrc_path
  rescue Exception
    warn "Could not load: #{ railsrc_path } because of #{$!.message}"
  end
end

class Object
  def interesting_methods
    case self.class
    when Class
      self.public_methods.sort - Object.public_methods
    when Module
      self.public_methods.sort - Module.public_methods
    else
      self.public_methods.sort - Object.new.public_methods
    end
  end
end

Paste into .irbrc file
In terminal > sublime ~/.irbrc