Found this great resource a few months back when it was in beta. There is a free version and a paid version.
SlideRocket was founded in 2006 by Mitch Grasso and Mike Lingle with the vision of building a better presentation experience, one that provides for every part of the presentation lifecycle and helps you make great presentations. SlideRocket is committed to providing the best presentation experience to individuals and businesses around the world through innovative and compelling software-as-a-service.
Check it out!