I'm a Rails developer with some Drupal 6 experience.
When I'm developing on Rails, I'm used to modifying my code and then relaunching:
cd /my/project/path
script/server
This will launch an instance of WEBrick, and my site will be available at http://localhost:3000, which is very convenient for testing - it doesn't require me to configure any Apache files and doesn't require admin rights.
In contrast now the only way I know for serving PHP pages is configuring an Apache virtualhost, which isn't as "agile".
Is there something as convenient as WEBrick, for PHP?