I use Zend Studio Professional to do all of my PHP work, nothing else even compares for PHP programming.
All of my PHP projects are commented with Zend-Friendly phpDoc style comments, making working on my PHP projects in Zend even easier.
I have setup the debugger on complex websites and used it to track down some very elusive bugs.
I have experience with Zend Platform and Zend Guard, and am currently playing with Zend Server.
I seem to be spending more and more time in flash these days. I just completed a plugin for Flowplayer for a 3rd party ad network.
I first started using Flash back when it was "Future Splash". I didn not do much with Flash again until recently, basically only
working with Flash programmers to develope applications (I would do all the server-side and HTML/JavaScript programming, they would do the Flash.)
But now that I have learned AS3, I find myself burning both ends of the candle. =)
topVisual Studio
I am currently using Microsoft Visual C# 2008 Express Edition for all of my C# applications. I actually haven not felt a real strong urge to upgrade
yet, but I am sure once I do, I will wonder how I ever lived without. I have become quite comfortable in the IDE and really miss it now when I work
on PHP projects!