require 'benchmark'

# The original implementation by Daniel DeLorme
# http://blade.nagaokaut.ac.jp/cgi-bin/scat.rb/ruby/ruby-talk/256662

class NilClass
   def ergo
     @blackhole ||= Object.new.instance_eval do
       class << self
         for m in public_instance_methods
           undef_method(m.to_sym) unless m =~ /^__.*__$/
         end
       end
       def method_missing(*args); nil; end
       self
     end
     @blackhole unless block_given?
   end
end

class Object
   def ergo
     if block_given?
       yield(self)
     else
       self
     end
   end
end

a,b = [1,2,3], nil
n = 100_000

Benchmark.bm(15) do |x|
  x.report("Original") do
    n.times { a.ergo[0];   b.ergo[0] }
  end

  # Turn to facets implementation
  require 'rubygems'
  require 'facets/nilclass/ergo'

  x.report("Facets") do 
    n.times { a.ergo[0];   b.ergo[0] }
  end

  x.report("Logic operators") do
    n.times { a && a[0];  b && b[0] }
  end
end

Benchmarking Object#ergo

Ruby