On Script-Tutorials.com today there's a new tutorial showing you how to use one of the more under-used and powerful features of recent PHP releases - the phar packaging for creating self-contained archives.
I guess you noticed that due your project become larger - the more and more files it contain. Sometimes it comes to the thousands of files. And then - Phar can help you. This utility allows us to pack a variety of files in the single library file. Thus, we can significantly reduce the number of include files in the project, and work with the entire library as with single file. It is also possible to have a packed (gzip/bzip2) version of the library.
They show you how to create simple phar archive (sample code here) that contains a few classes linked by an index.php file.