Setting up an OS X development server

Okay, so this was very much a case of fumbling around in the dark until stuff worked, lot’s of Googling and breaking stuff. The end result is a dev server on OS X that is running Textpattern with clean URLs and a copy of WordPress for good measure. These notes are primarily so I don’t forget how I did it, if they are useful to someone else, great! Be warned, though, I have no idea how secure this set up is and what flaws it has, so you follow these instructions at your own risk! Also, I am using OS 10.3.9 so I don’t know if this would work on Tiger.