1. The sharing method that is right under most Internet users' noses is Google Docs presentation sharing. Students can create presentations, collaborate on presentations, chat about presentations, and publish presentations using Google Docs. Google Docs presentations can be embedded into any blog or website. Students can also share presentations by emailing or Twittering the url of their presentations.
2. Empressr is a fully functional, high quality, online slide show presentation creation and sharing service. Empressr has a couple of features differentiating it from its competitors. The first feature of note is the option of embedding video from multiple sources into your slide show. The second feature of note is Empressr's editor which allows users to draw, create, or edit images inside their slides. Empressr slideshows can be embedded anywhere.
3. SlideShare is probably the most popular service for publishing slideshows to the web. While you cannot create original works in SlideShare, you can add voice narration to your slideshow with a free service offered by SlideShare. SlideShare offers a variety of widgets for embedding collections of slideshows into one webpage. If you wanted to you could create a collection of your students' slideshows and put them into one widget on one webpage. To learn more about SlideShare, watch this presentation.
4. Slide Boom, like SlideShare, allow users to upload their slide show presentations and share the slide shows publicly or privately. SlideBoom quickly converts your slide shows for use on the SlideBoom website and provides the html code for use on other websites or blogs. SlideBoom preserves the transitions you included in your original presentation when your slideshow is uploaded to SlideBoom.
5. Slide Rocket is a web based presentation creator similar to Empressr. Slide Rocket has some very nice features like 3D transitions and a collaboration feature for sharing the creation process with other users. Slide Rocket's interface is user friendly making it easy to include videos, pictures, or third party plug-ins. The quality and definition of images on Slide Rocket is far superior to that found in many of its competitors' offerings.
6. Author Stream is a service that converts your PowerPoint slideshows to flash media files. Just like SlideShare, Author Stream can be used to host and share your slide shows publicly or privately directly on the Author Stream website. In addition to sharing on the Author Stream website the slideshows you upload can also be shared via Youtube, iTunes, or embedded into a blog or website. A free companion tool to Author Stream is Author Point Lite. Author Point Lite is a desktop application that converts Power Point files to flash files. Files converted with Author Point Lite retain all of the transitions, timings, and narration created in your original file. Author Point Lite is a free download.
7. If you convert your slideshows into PDF format, you can upload them and host them on DocStoc and Scribd. Both DocStoc and Scribd will provide you with an editable (for height and width) embed code for your PDF.
8. Hello Slide is a tool that you can use to add voice narration to slides that you display online. Hello Slide is different from services like Slideshare's Zipcast because instead of recording your voice you type what you want the narrator to say. Where you might type "speakers notes" in other slide programs, in Hello Slide you type out the narration. Hello Slide creates the audio and narrates your slides for you. While the voice is slightly robotic, it is much much better than most text to speech services. To get started using Hello Slide, register for a free account, upload a PDF of your slides, then start typing your narration. It's very easy to use Hello Slide.