Include this from your rakefile to get a (Windows) growl notification when rake process completes

growl.rb

unless ENV["BUILD_NUMBER"] # do not use growl when running on the CI server
  
task :growl do
  Rake::Application.growl
end

module Rake
    class Application
        # override task execution so that growl task is always called last
        alias :raw_top_level :top_level

        def top_level
            followed_by :growl do
                raw_top_level
            end
        end

        def self.growl(err_message=nil)
          message = err_message || "Rake complete"
          growl_type = err_message.nil? ? "Complete" : "Fail"
          priority = err_message.nil? ? 0 : 1
          icon = err_message.nil? ? "dt-logo-60.png" : "icon-unread.png"
          RakeFileUtils::verbose(false) do
            sh "tools/growl/growlnotify.exe /r:\"Complete\",\"Fail\" /a:\"rake\" /t:\"rake\" \"#{message}\" /n:\"#{growl_type}\" /p:#{priority} /i:\"../../source/DovetailCRM.Web/Content/images/#{icon}"
          end
        end

        # override exception handling to send a growl notification
        def standard_exception_handling
          begin
            yield
          rescue SystemExit => ex
            # Exit silently with current status
            raise
          rescue OptionParser::InvalidOption => ex
            # Exit silently
            exit(false)
          rescue Exception => ex
            # Exit with error message
            $stderr.puts "#{name} aborted!"
            $stderr.puts ex.message
            if options.trace
              $stderr.puts ex.backtrace.join("\n")
            else
              $stderr.puts ex.backtrace.find {|str| str =~ /#{@rakefile}/ } || ""
              $stderr.puts "(See full trace by running task with --trace)"
            end
            Application.growl ex.message
            exit(false)
          end
        end
        
        def followed_by(*extra_tasks)
            orig_task = top_level_tasks.dup
            @top_level_tasks = top_level_tasks + extra_tasks
            yield
            @top_level_tasks = orig_task 
        end
    end
end

end