"Twit This" service for Mac OS X

Twit This Service.rb

#!/usr/bin/env ruby
# Get ThisService from http://wafflesoftware.net/thisservice/
# Use this .rb file with Type: "Acts on Input" and click "Create Service"
# From now on, you can twit the selected text in *any* Cocoa application by
# selecting Application menu » Services » Twit This
# 
# The first time you use it you'll be prompted for authorisation to use your
# saved user and password from Keychain.app

input = STDIN.gets nil

data = `security find-internet-password -s twitter.com -g 2>&1`

if data =~ /^password: "(.*)"$/
  password = $1
end

if data =~ /"acct"<blob>="(\w+)"/
  user = $1
end

%x(curl -d 'status=#{input}' -u #{user}:#{password} http://twitter.com/statuses/update.atom)