This is quite a big list and a very good one at that. The title should be '50 Useful PHP Tools' to emphasize that it's not just another small list of PHP tools.
The categories covered are as broad as the list is long:
* Debugging Tools
* Testing and Optimization Tools
* Documentation Tools
* Security Tools
* Image Manipulation and Graphs
* PHP Code Beautifier
* Version-Control Systems
* Useful Extensions, Utilities and Classes
* PHP Online Tools and Resources
* In-Browser Tools (Firefox Add-Ons)
* Frameworks for PHP
* PHP IDEs and Editors
A list like this would have saved me somuchtime when I started using PHP. Then again, most of this stuff didn't even exist when I started using PHP.
A little shout-out to two PHP tools I love that weren't mentioned:
The Kohana framework - An offshoot of CodeIgniter, only written for PHP 5. It's cleaner, with generally fewer surprises and (I'm fairly certain) faster.
http://kohanaphp.com/
Komodo Edit/IDE - A general-purpose IDE written by the folks at ActiveState. Even the free Edit version is the best PHP editor I've used yet.
http://www.activestate.com/komodo/
Some of the categorisation is a little unusual with libraries, PEAR, and templating systems, Smarty and Savant2, thrown in with frameworks and the version control section containing only continuous integration tools. It's a good list though.
The categories covered are as broad as the list is long:
A list like this would have saved me so much time when I started using PHP. Then again, most of this stuff didn't even exist when I started using PHP.