Nice list! To underoverflow's comment, BitNami offers a library of free appliances (as well as native installers and templates / AMIs for the Amazon Cloud) for the top open source applications. We currently offer over 50 apps, including the Moodle appliance listed above (we also have LAMP, Drupal and WordPress, which are also listed above.) All of the installers, appliances and cloud templates are fully configured, free, and ready-to-run. We also update them very regularly, so you can always get access to the best and latest versions. You can get them from: http://bitnami.org/stacks Note that they are categorized by type of application on the left hand side of the page to make it easier to find new apps.

Disclaimer: I work for BitNami.