Well, here I'm going to write about a great library that didn't get enough attention as it deserves, I mean Net_SmartIRC, is a complete library that conforms to the RFC 2812 (IRC protocol).

This library is enough for writing a bot but there's also a great framework (phpbitch) that has more features to and writing new modules for it isn't a pain..

Not only does Net_SmartIRC boast an impressive list of features, but the phpbitch application based on it already has several modules that come bundled with it, including an interface to Google, logging abilities, user management, and a PHP manual search.