This article covers some advanced uses of the language and shows some tricks that make PHP an extremely useful language to work with. Unlike Darrel's article [here] however, this one will also cover the Windows version of PHP as well as the Linux/Unix one.
They compare the two operating environments, noting what can and can't be done in each before getting to some of the "neat things" that pipes let you do. They show who to read from stdin (making it easy to pass the results from another command in) and what you can do with the results. Near the end there's also a bit included showing how to do a similar thing on windows (with the help of an external tool).