Yes authorstream is awesome for power point presentation. Also Wiziq is also a power point presentation platform. Wiziq has a Moodle Plug in that lets you go directly into its virtual classroom.
This might prove helpful to you.
With your interest in Technology Integration, I recommend you take a look at Wiziq's virtual classroom and authorstream's power point presentation platform. Both are web based platforms, have a bunch of features and free basic service. Here’s a public class recording conducted by Nellie Deutsch on Technology Integration.