I've seen somewhere a presentation that was written entirely in HTML, CSS and Javascript. It was "properly" structured, so that if you'd view it with Lynx it would look like a normal document, yet in Firefox (and others, I suppose) it looked like a Powerpoint presentation, with added "back" and "forward" buttons.
Does anyone know what tool can be used to create such presentations? Or where I can find examples of such presentations on the web? Google fails me at the moment.