gistfile1.rb

#!/usr/bin/env ruby
# a/b/c.mp3 -> a/b/a-b-c.mp3
require 'pathname'
require 'fileutils'
require 'enumerator'

include FileUtils::Verbose

src = Pathname.new(ARGV.shift)
dst = src.enum_for(:each_filename).inject([]) do |memo, filename|
  memo << filename if filename !~ /^\.+$/
  memo
end.join('-')

mv src, src.dirname + dst