Hi Everyone,
I just thought I'd provide links to the software that I've used for testing PHP/MySQL applications. The first is a USB Flash Drive based web server. It can be found at:
http://www.chsoftware.net/en/useware/mowes/mowes.htm
Unfortunately, it's only for PC's.
However, this next reference is for Komodo Edit from ActiveState and it runs on PC's and Macs. It's a great environment to develop PHP or most any other language that may not have a standard editor, and it beats using vi on a Mac. It can be found at:
http://www.activestate.com/komodo_edit/
I hope this helps.