SpeakingImage

SpeakingImage allows you to create interactive images on online and then share them with others. You can also create groups, add wikis and set different permissions to manage collaborative work. You can set markers on the work or add lines and polygons to highlight a point or fact. This is a great tool for highlighting details in a complicated image to your students, It could be used in art, science and technology classes really easily but I can see uses for this in most subject areas.

Each of the annotation has its own wiki connected to it so your class or group can continue to add articles or further information connected to the images.

http://www.speakingimage.org/