Marked.js - A full-featured markdown parser and compiler, written in JavaScript. Built for speed.
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.
Markdeep - Advanced Markdown renderer for the browser with full diagram support
Google Slides - Create a new presentation and edit it with others at the same time — from your computer, phone or tablet. Free with a Google account.
ShowdownJS - A Markdown to HTML converter written in JavaScript
Keynote - Keynote for Mac, iOS, and iCloud lets you make dazzling presentations. Anyone can collaborate — even on a PC. And it’s compatible with Apple Pencil.