The problem with PowerPoint and KeyNote and the like is that they don't really have a good workflow for when you need to produce a quick presentation in the five minutes before your slot comes up. Too heavy, too many choices, too much animation and clipart.
Slider solves those problems and more with a simple text-oriented workflow for creating and sharing slide presentations.
Try it out here: https://guitarvydas.github.io/slider/
The Slider edit interface shows a list of your slides down the left, and a preview of the current slide on the right. As you change text in the slide list, the preview updates.
You can add new slides to the end with the "+ slide" button. Start the presentation (hide the edit interface) with the "show" button. Each slide shows a label and buttons for moving the slide up, duplicating it or deleting it. (Note: Currently no undo...)
When you start your presentation, the slide view takes up the full page. Use your browser's full-screen mode (e.g. [f11] on FireFox) for best effect.
Navigation controls are provided on the lower third of the screen, or you can use the [pgup] and [pgdn] keys to step through the slides.
Every time you move to a new slide, the current presentation is encoded into the current URL. Just copy the URL and email it, drop it into chat or put it on your profile page -- when the recipient clicks on the link, they'll see your presentation.