I've heard many people say that they can't see the usefulness of Ruby 2.0's new `Module#prepend`. IMO, it can be very useful. This is a good example of that.

simple-method-benchmark-example.rb

class Hello
  def world
    puts 'Hello world!'
    sleep 1
  end
end

SimpleMethodBenchmark.wrap! Hello, %i{world}

hello = Hello.new

hello.world

simple-method-benchmark.rb

class SimpleMethodBenchmark
  module Wrapper; end

  def self.wrap! klass, method_names
    method_names.each do |method_name|
      Wrapper.module_eval do
        define_method method_name do
          full_method_name = "#{klass.name}##{method_name}"
          line             = ('-' * 35)

          benchmark_begin = Time.new

          super()

          benchmark_end   = Time.new
          benchmark_total = (benchmark_end - benchmark_begin)

          puts
          puts ' Method benchmark:'
          puts " > #{full_method_name}"
          puts
          puts line
          puts " Begin: #{benchmark_begin}"
          puts " End:   #{benchmark_end}"
          puts " Total: #{(benchmark_total * 1000).round 5} millisecond#{'s' if benchmark_total != 1}"
          puts line
          puts
        end
      end
    end

    klass.class_exec do
      prepend Wrapper
    end
  end
end