Drupal's multi-site capability provides a useful way to save disk space and reduce maintenance. At a certain point, however, it becomes more cumbersome to manage upgrades, test new modules, and fix problems with out affecting all the other sites in a multi-site. With Aegir you can reduce unintentional downtime, errors, and save yourself a ton of time in maintenance. I'll show you some of the way's I've used Aegir to improve my workflow, and most importantly, save time.
(somewhere between beginner and intermediate)