I have created a PHP system for easy push messages from i.e. an arduino with network access.
The PHP system handles the request from the arduino, then processes what to do with it.
For my snailmail notifier, I have put a line like "%HITS% time today, %sincelast% since last time." in, and it will then show up on my phone or email as "7th time today, 00:18:08 since last time.".
There are also options to put more things into each message, but you can try that for yourself.
Requirements is PHP and a MySQL database.
If you want to send push messages to an iPhone you can then use either Prowl or Notifo to deliver the messages. Email would be to just put the address into the config.inc.php, where you also put the other info in.
Notice, it is version 0.1 RC, so there can still be many bugs and much room for improvements, but as it is open source too, you can edit and fix things if you find any problems, or have a better way to do something. And feel free to share it, it might get into a later version
Get it here: http://bld.is-a-geek.com/2011/01/18/php-notices/