Came up with a great little extension today for the Symbol class. One
that also shows off Facets' Functor class:

  require 'facets/functor'

  class Symbol

    # Convert symbol to string, apply string method
    # and convert back to symbol via a fluent
    # interface.
    #
    #   :HELLO.re_s.downcase  #=> :hello
    #
    def re_s
      @re_s ||= Functor.new do |op, *a|
        to_s.send(op, *a).to_sym
      end
    end

  end

I picked the name 're_s' off the top of my head. I'm open to better
suggestions.

T.