How do I use define_method to create class methods?

I think in Ruby 1.9 you can do this:

class A
  define_singleton_method :loudly do |message|
    puts message.upcase
  end
end

A.loudly "my message"

# >> MY MESSAGE

This is the simplest way in Ruby 1.8+:

class A
  class << self
    def method_name
      ...
    end
  end
end

I prefer using send to call define_method, and I also like to create a metaclass method to access the metaclass:

class Object
  def metaclass
    class << self
      self
    end
  end
end

class MyClass
  # Defines MyClass.my_method
  self.metaclass.send(:define_method, :my_method) do
    ...
  end
end