PHP logging library that sends logs to files, sockets, email, databases and web services via a PSR-3 compatible API.
OWASP Mutillidae II is a free, open-source, deliberately vulnerable web application providing a target for web-security training. This is an easy-to-use web hacking environment designed for labs, security enthusiasts, classrooms, CTF, and vulnerability assessment tool targets.
JSON Lint for PHP
PHAR file format utilities, for when PHP phars you up.