Impress.js: The death by PowerPoint… and Prezi
Inspired on Prezi, Impress.js is a free and open source alternative that let you design free presentations using HTML5 and CSS3.
The source code is available on Github and you can start using Impress.js as a Javascript library. With Impress.js you can create amazing and wonderful 3D animated presentations, although there isn’t an online editor to make your presentation so you’d need (for now) some technical skills.
Basically Impress.js can be defined as a presentation framework that takes its inspiration from Prezi, another popular presentation platform but using web standards and open source project. Check out the source for impress.js on GitHub.
If you ware curious to learn more about web standards and presentations, you can check the Wikipedia article web based slideshow.