authorSTREAM - authorSTREAM enables presenters to upload & share PowerPoint, Keynote & PDF presentations online; embed in blogs, convert to video and share on social networks.
Zentation - Affordable webinar software. Create online presentations with synchronized video and PowerPoint.
projeqt - With Projeqt, your presentations never remain static. Pull in live tweets or blog feeds, insert an interactive map, add audio notes or stream videos. Let your presentations be as dynamic as you are.
SlideWorld - Slideworld offers a wide collection of professionally made PowerPoint designs to enhance your PowerPoint presentation, saving you ample time.
Prezi - Welcome to Prezi, the presentation software that uses motion, zoom, and spatial relationships to bring your ideas to life and make you a great presenter.
SlideShare - Discover, Share, and Present presentations and infographics with the world’s largest professional content sharing community.