My .irbrc for console/irb

I recently discovered that I can create a .irbrc file to run setup for
my irb/console. I am in love.

My current .irbrc is:

require 'irb/completion'
require 'map_by_method'
require 'what_methods'
require 'pp'
IRB.conf[:AUTO_INDENT]=true

Explanation of the different libraries:
http://drnicwilliams.com/2006/10/12/my-irbrc-for-consoleirb/

Does anyone any interesting things in their .irbrc file?

Nic

http://wiki.rubygarden.org/Ruby/page/show/Irb/TipsAndTricks