One of our testers, who is infinitely more talented than I am, created a video using PowerPoint. It's really quite cool, and there are some good tips in there for extending your PowerPoint-fu to make better presentations. You can see his video in his Mac Mojo post A Dog's Day: A PowerPoint Short Film, which has the video itself and some screenshots along the way.
He's also uploaded his presentation to Art of Office. His presentation makes use of motion paths, which we introduced in Office 2008 SP2, so make sure that you're updated before you try to play around with his presentation.