Presentz is a JavaScript library that allows us to synchronize videos and slides however we want.

The library is handy for anyone that prepares/makes presentations or for any website that uses videos and slides side-by-side (mostly, landing pages).

Presentz - Video and Slide Synchronization

It has support for YouTube, Vimeo or self hosted videos and slides from Slideshare, Speakerdeck, Rvl.io, your own Flash files or images.

The project has actually 2 parts, presentz.org (its source), the website with an editor which allows us to create such slideshows freely and the Prezents.js (JS library) where both are open source.