OpenSource CMS has completely revamped its site and now includes easy access to dozens of PHP/MySQL-based Content Management Systems. Now you can try before you install.
The administrator username and password is given for every system and each system is deleted and re-installed every two hours. This allows you to to add and delete content, change the way things look, basically be the admin of any system here without fear of breaking anything.
The list includes Drupal, which this site runs on, and two others that I have used, Tikiwiki and Mambo. There are also some elearning CMS, like ATutor (which I have used) and Moodle (which I will soon be using). This is one big virtual sandbox for you to play in.
