DZone.com: Automated code reviews for PHP
On the Web Builder Zone (a part of DZone.com) Giorgio Sironi take a high-level look at some of the tools you can use for automated code reviews in your projects without you ever having to lift a finger (well, once it's set up, of course).
I'm exploring an approach to automated code review: it's not as precise as the human-based one, but it scales better. [...] All in all, automated code reviews, performed with tools instead of with human intellect, can be a starting point to search for the problematic zones of a codebase. Then the human may come in, since they also have to clean up the code: their intervention was already scheduled.
The tools he mentions (and, in some cases, shows how to install/use) are: