drush_make

Aegir is a pretty powerful tool that allows you to very quickly provision new Drupal sites out of the box and manage them throughout their lifespan through a variety of tasks.

Its ability to understand different install profiles and thus 'distributions' shoots the awesome factor through the roof once you can deploy instances of OpenAtrium, Pressflow, ManagingNews or your own custom distro in just a couple of clicks.

I did a screencast on how you can use Drush Make to generate 'builds' based on Drupal core, with optional components such as install profiles + module/theme/library dependencies. The example given is the Managing News news aggregation system.

I then show how you can add the build as a Platform in Aegir, and rapidly provision sites on it in a multisite structure.

After noticing that in the community, some people are seeking a central community 'hub' Feature Server via which to upload and share their Features, I bought featureservers.org and set up http://community.featureservers.org to do exactly that.