My .irbrc and .railsrc files.

.irbrc

#!/usr/bin/ruby

# Add all gems installed in the system to the $LOAD_PATH so they can be used in Rails console with Bundler
if defined?(::Bundler)
  current_ruby_version = `rbenv version`.split(" ").first
  gem_paths = Dir.glob("#{ENV["HOME"]}/.rbenv/versions/#{current_ruby_version}/lib/ruby/gems/**/gems/*/lib")
  gem_paths.each do |path|
    $LOAD_PATH << path
  end
end

require 'irb/completion'
require 'irb/ext/save-history'

IRB.conf[:SAVE_HISTORY] = 1000
IRB.conf[:HISTORY_FILE] = "#{ENV['HOME']}/.irb_history"

IRB.conf[:PROMPT_MODE] = :SIMPLE

%w[rubygems looksee wirble pp map_by_method what_methods].each do |gem|
  begin
    require gem
  rescue LoadError
    puts "Failed to load #{gem}"
  end
end

# Wirble settings
begin
  Wirble.init
  %w{init colorize}.each { |str| Wirble.send(str) }
rescue
  puts "Wirble unavailable"
end

class Object
  # list methods which aren't in superclass
  def local_methods(obj = self)
    (obj.methods - obj.class.superclass.instance_methods).sort
  end
  
  # print documentation
  #
  #   ri 'Array#pop'
  #   Array.ri
  #   Array.ri :pop
  #   arr.ri :pop
  def ri(method = nil)
    unless method && method =~ /^[A-Z]/ # if class isn't specified
      klass = self.kind_of?(Class) ? name : self.class.name
      method = [klass, method].compact.join('#')
    end
    system 'ri', method.to_s
  end
end

def copy(str)
  IO.popen('pbcopy', 'w') { |f| f << str.to_s }
end

def copy_history
  history = Readline::HISTORY.entries
  index = history.rindex("exit") || -1
  content = history[(index+1)..-2].join("\n")
  puts content
  copy content
end

def paste
  `pbpaste`
end

railsrc_path = File.expand_path('~/.railsrc')
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

# Break out of the Bundler jail
if defined? Bundler
  Gem.post_reset_hooks.reject! { |hook| hook.source_location.first =~ %r{/bundler/} }
  Gem::Specification.reset
  load 'rubygems/custom_require.rb'
end

.railsrc

#!/usr/bin/ruby

begin
  require 'hirb' # sudo gem install cldwalker-hirb --source http://gems.github.com
  Hirb.disable
rescue LoadError
end

def sql(query)
  ActiveRecord::Base.connection.select_all(query)
end

def change_log(stream)
  ActiveRecord::Base.logger = Logger.new(stream)
  ActiveRecord::Base.clear_active_connections!
end

def show_log
  change_log(STDOUT)
  true
end

def hide_log
  change_log(nil)
  true
end

hide_log  # Start hidden

def load_lib
  path = File.join( Rails.root, 'lib') 
  failures = []
  Dir.glob("#{path}/**/*.rb").each {  |file|
    #puts "loading: #{file} ... "
    begin
      load file
    rescue => ex
      failures << file 
    end
  } 
  # this second pass is here to try to catch anything that 
  # is dependent on something else
  # could be improved, but is working fine for my needs
  double_failures = []
  for file in failures 
    begin
      load file
    rescue => ex1
      double_failures << file 
    end
  end 

  if double_failures.size > 0 
    puts "these files failed twice"
    for file in double_failures
      puts file
    end
  end 
end