Apache/PHP/MySQL
Back in the days of Mac OS X 10.0, setting up a dynamic webserver was an ordeal. I was new to Unix at the time and installing PHP and MySQL required compiling both from source and recompiling Apache as well. Not only that, but MySQL’s build kept failing until I fdiscovered (thank you Google) that two lines of code had to be changed in one of the source files. Since that time things have gotten much simpler. I have installed PHP/MySQL numerous times and it gets easier every time.
Entropy.ch has PHP in a Mac OS X package - just download it and run the installer. MySQL also has packages for Mac OS X (also linked to from entropy.ch). MySQL now has a Preference Pane for System Preferences included in the Mac download! Don’t forget to download the ImageMagick package if you want to manipulate images in PHP (or use things like Typo3 or Gallery). Last night I set up a dynamic webserver in about 10 minutes.