CoSketch: A Simple Collaborative Online Whiteboard

You can find a lot of multi-user whiteboard collaboration tools online today but most of them offer the same functionality. These types of web apps allow you to easily share your ideas by using drawing tools. CoSketch is a similar tool but it has a couple of nice features that you cannot easily find anywhere else.

http://www.makeuseof.com/dir/cosketch-collaborative-online-whiteboard/