DocDroid - DocDroid is a service for sharing document and slides.
VCASMO - VCASMO is a multimedia presentation solution for photo and video slide shows, business presentations, training, academic teaching, sales pitches, and seminars.
SlideShare - Discover, Share, and Present presentations and infographics with the world’s largest professional content sharing community.
DocSlide - DocSlide is an online document and knowledge sharing platform.
projeqt - With Projeqt, your presentations never remain static. Pull in live tweets or blog feeds, insert an interactive map, add audio notes or stream videos. Let your presentations be as dynamic as you are.
Speaker Deck - Speaker Deck is the best way to share presentations online.