Movenote is a new web-based service which allows you to bring together video and presentations into one show.
You first upload all of your images or presentation files and then as you flip through them you record your own video via your webcam. It supports presentation files, PDFs, Excel files and more and after you have uploaded your slides you can re-order them in any you want.
You can also upload an already recorded video and play the slides in sync as the video plays.
The final video + images show can be shared via a URL link for via a full embed code provided by the system.
The service is free.
My test presentation: http://www.movenote.com/v/0Ho
The hidden sign-up page is here: http://www.movenote.com/user/register ;-)