In a post a little while back, Padraic Brady wrote about an extension he whipped up to act as an interface between PHP and the Snarl notification tool (inspired by Growl from OS X).

My intention for the API is to facilitate Window's use of a soon to be announced tool for autotesting in PHP using PHPSpec.

He wants to use it in an automated testing environment that, when tests are detected in the current tests, runs the changed items and reports back the results via the Windows notification service. You can grab the code from the Google Code repository for it and test it our for yourself.