Aegir is a distributed provisioning system for Drupal that allows you to manage thousands of sites across as many concurrent instances of Drupal on as many servers as you need. At Koumbit Networks, a lead development shop behind the Aegir project, we are developing or already have in place several distinct business models, largely enabled by our Aegir infrastructure and expertise.

For our "classic" web development practice, Aegir provides for a streamlined development-staging-production workflow, as well as scalability and flexibility. I won't go into extensive detail on this model, except to point out the abundant resources already available on community.aegirproject.org and elsewhere.

With the introduction earlier in the year of .deb packaging for Aegir, we've begun to put in place an Infrastructure-as-a-Service (IaaS) offering. While various automated install scripts have existed for years, they've tended to be somewhat brittle. Now proper configuration management (Puppet, Chef, etc.) can set up and maintain virtual servers with Aegir pre-installed in an extensible templated fashion.

Longer-term, and more ambitiously, we are developing a Platform-as-a-Service (PaaS) offering, that will enable site developers and designers to create and manage their own custom Drupal instances and platforms from within a managed Aegir system. This will allow for not only automatic provisioning, and management of sites and custom platforms, but also the secure, automated set-up of SFTP, SSH, etc. This opens the door to a variety of interesting reseller program possibilities.

Finally, leveraging e-commerce integration and other contrib modules, we are sponsoring development of a Software-as-a-Service (SaaS) model. This allows clients to purchase subscriptions to pre-built sites (whether pre-packaged profiles such as Open Atrium, or custom-built profiles based on the best websites you've created), which are then provisioned for them by an Aegir system. This model presents some interesting challenges, which I'll explore in more detail by demonstrating going from a bare-bones Aegir install, though to a basic, but functional SaaS service, ready to be themed and extended