For some more SPL examples, read through the source of the KohanaPHP framework (http://www.kohanaphp.com http://www.kohanaphp.com). The framework was originall

For some more SPL examples, read through the source of the KohanaPHP framework (http://www.kohanaphp.com http://www.kohanaphp.com). The framework was originally a fork of CodeIgniter, but has evolved into a completely new and powerful framework -- completely written in PHP5. The framework source is very well written and has some excellent examples of using SPL and OOP along with some nice helpers and libraries.