Because customizing config.php is insufficient (3rd party code get left out, config.php get overwritten on update, ...) http://boblet.tumblr.com/post/68095239/ee-localhost

ee-localize-mysqldump.rb

#!/bin/env ruby
if ARGV.empty?
  $stderr.puts <<-EOM

  ExpressionEngine (1.x) MYSQL DUMP Localizer

  1. Reads MYSQL DUMP of ExpressionEngine website from STDIN
  2. Replaces ALL HOSTNAME & PATH data (config) with LOCAL SETTINGS
  3. Output corrected MYSQL DYMP file.

  Usage arguments: <hostname> <document_root> [url_basepath: default '/']

  Examples:
    ruby #{__FILE__} www.livewebsite.com /var/www /         < mysqldump.foreign.sql > mysqldump.local.sql
    ruby #{__FILE__} localhost:8888 /var/www /livewebsite/  < mysqldump.foreign.sql > mysqldump.local.sql

  EOM
  exit(1)
end

# 1. sanitize arguments
hostname, documentroot, urlbasepath = ARGV
hostname = hostname.to_s.gsub(/^\/+|\/+$/, '')          # no trailing slash
documentroot = documentroot.to_s.gsub(/^\/+|\/+$/, '')  # no slashes before and after
urlbasepath = "#{urlbasepath.to_s}/".gsub(/\/\/+/, '/') # with trailing slash

# 2. configure all possible configs based on your different environments
map = {
  "/livewebsite/"              => urlbasepath,
  "localhost:8888"             => hostname,
  "localhost:8888/livewebsite" => hostname,
  "var/www"                    => documentroot,
}

# 3. removing circular reference
map.delete hostname
map.delete documentroot
map.delete urlbasepath
# 4. these key-values are sorted so that the lengthier keys are matched first
map = map.sort {|(k1,v1),(k2,v2)| k2 <=> k1 }

map.each do |key,val|
  $stderr.puts "Will replace #{key} -> #{val}"
end

# 5. wait for regrets
sleep 5
begin
  while line = STDIN.readline
    line.chomp!
    map.each do |key,val|
      # 6. First, we try to look for PHP#serialize'd strings and replace those values (with corrected string length header)
      r = Regexp.new(/(s:(\d+):(\\"(((?!\;s\:).)*?#{Regexp.escape(key)}((?!\;s\:).)*?)\\";))/)
      $stderr.puts r if line.match(r)
      while line.match(r)
        match = $1
        newval = $4.gsub(key, val)
        $stderr.puts "\t" + match
        replace = ('s:' + eval('"' + newval + '"').length.to_s + ':\"' + newval + '\";')
        line.gsub!(match, replace)
        $stderr.puts "\t" + replace
        $stderr.puts
      end
      # 7. Next, we replace any other occurrences which are not PHP#serialize'd
      line.gsub!(key, val)
    end
    puts line
  end
rescue EOFError
  # file has ended. it is ok
end