I recently had to set up a new mac for web development.
Its always such a hassle to find it all again and I ended up spending much more time then anticipated.

Here is a quick reference list of what steps I took. Following this list will get you going in under one hour plus all software is free.

1. install cyberduck for transfer and remote synchronization
2. install xampp for a complete LAMP setup
3. install eclipse pdt for a great php IDE
4. install eclipse subclipse plugin for your svn projects
5. install aptana plugin for all web development
6. install textwrangler as a general purpose text and code editor with remote support
7. install firefox with firebug plugin for debugging your html/css/javascript

After that also download some great php libs to include in new php projects:

1. redbean – database orm
2. ezql – easy database interface and abstraction
3. phpmailer – probably the best email lib for php
4. phpunit – unit testing
5. simplepie – rss parser and rss creation
6. php thumbnails – great for image uploads