Renames all files in the current dir using their MD5 checksums.

md5rename

#! /bin/bash

md5 * | sed -e 's/MD5 (\([^.]*\)\(.[^)]*\)) = \(.*\)$/mv -v "\1\2" \3\2/' | sh

md5renamer.rb

#! /usr/bin/env ruby

require 'digest/md5'

def rename_file(file)
  old_name = File.basename(file)
  new_name = Digest::MD5.hexdigest(file.read) << File.extname(file)
  File.rename(file, new_name)
  puts "#{old_name} => #{new_name}"
end

# Script starts!
files = Dir.glob("*.{jpg,jpeg,png,gif}") # Currently limited to images!
files.each { |file| rename_file File.open(file) }