I decided to stop using it a long while ago and move on, but it's still quite popular.
- Pharen a LISP that compiles down to PHP.
- Cake - a Rails-inspired framework
- Mojavi, one of many MVC frameworks for PHP
- Popoon - another Cocoon-inspired library, for PHP5
- Propel, an object persistence library.
- log4php a port of the log4j Java logging framework
- phpHtmlLib - excellent base toolkit
- PECL packages for:
Of Special Note:
- Nanoweb - PHP as its own HTTP server.
- Turck MMCache (a free Zend-like optimizer)
- eAccelerator - another optimizer
- IlohaMail - neat and efficient webmail