Gretastudio is a brand-new site that lets you upload a PowerPoint presentation, easily add audio and/or video to it, and then post a link to it on the Web (it doesn’t appear that you can embed it, though).

It’s in an “invitation-only” mode right now, but I received one minutes after I requested it, so you shouldn’t have long to wait.

It’s not as accessible to English Language Learners as, let’s say, VoiceThread, but it does have some advantages.

I’ll be placing a link to it on my website after it becomes fully open to the public.