Prezi
A cross between a whiteboard and a slide show, Prezi allows students to share all types of media in their presentations. Prezi is still evolving and has recently added voice over capability. Prezi can be collaborative. Caution your students to avoid excessive zooming! Here is a Prezi on the use of Cartoons in school.
Mural.ly
Collaborative and visual! Create a Mural.ly, invite collaborators, add images, video, text, comment, and discuss the project in chat. Here is a sample Mural.ly I created on the digestive system.