On JavaWorld they've posted a look at command-line PHP support including a few sample scripts to get you started:
When I decided to give PHP a closer look, I wondered if PHP was a browser-only technology or if it could be used for command line scripting. It turns out that one can write operating system level scripts with PHP as discussed in online resources such as Command Line Scripting in PHP, Command Line PHP on Microsoft Windows, and Executing PHP files. In this blog post, I look at PHP command line scripting at an introductory level.
He talks about some of the basics - setting up a "Hello World" script to be run as PHP (and running it) as well as adding in the ability to take command-line arguments. He shows how to get environment information and run other command calls through the PHP script. He also points out the handy php_sapi_name method that can be used to detect whether or not the script is running on the command line.