SlideCamp - Library of PowerPoint slides to kickstart your presentation.
Draftsend - Presentations you can 👀 and 👂
Slidebean - Presentations that design themselves
Slides - Slides is a place for creating, presenting and sharing presentations. The Slides editor is available right in your browser. Unlike traditional presentation software, like PowerPoint, there's no need to download anything.
SlidesPPT - Beautiful free presentation templates for Google Slides
Reveal.js - A framework for easily creating beautiful presentations using HTML