Script to notify you of new issues you're participating in via growl. Just pass it your drupal.org user id as the first arg.

drupal_issue_notify.rb

#!/usr/bin/env ruby
require 'rubygems'
require 'rss/1.0'
require 'rss/2.0'
require 'zlib'
require 'open-uri'
require 'ruby_gntp'
require 'tempfile'

def store_dump(filename, obj)
  marshal_dump = Marshal.dump(obj)
  file = File.new(filename,'w')
  file = Zlib::GzipWriter.new(file)
  file.write marshal_dump
  file.close
end

def load_dump(filename)
  begin
    file = Zlib::GzipReader.open(filename)
  rescue Zlib::GzipFile::Error
    file = File.open(filename, 'r')
  ensure
    obj = Marshal.load file.read
    file.close
    return obj
  end
end

if ARGV.length > 0
  begin
    user_id = Integer(ARGV[0])
  rescue ArgumentError
    abort("Must provide a valid drupal.org username!")
  end
end

feed = "http://drupal.org/project/issues/user/#{user_id}/feed"
rss = RSS::Parser.parse(open(feed))
filename = "#{Dir.tmpdir}/do-notify.marshal"
prev_rss = load_dump(filename) if FileTest.exists?(filename)
new = []

# Loop through the new feed items and compare them to what we have stored.
rss.items.each_with_index do |item, index|
  is_new = true
  unless prev_rss.nil?
    prev_rss.items.each_with_index do |prev_item, i|
      if prev_item.guid.content == item.guid.content
        # If the guid is the same but the date is different, consider it new.
        if prev_item.date.to_i == item.date.to_i
          is_new = false
        end
      end
    end
  end
  # If we haven't found a matching feed item in the stored feed, consider it new.
  new << item if is_new

  # Don't try to show more than 5 at a time.
  break if index > 5
end

new.each do |n|
  GNTP.notify({
    :app_name => "D.O. Notify",
    :title    => "D.O. Notify",
    :text     =>  n.title,
    :icon     => "http://drupal.org/files/druplicon.small_.png",
    :sticky   => true,
  })
end

store_dump(filename, rss)