Scribblar, a collaborative whiteboard tool, has recently made two significant enhancements to its service. First, Scribblar now has an equation editor built into the toolbar. Second, Scribblar has added the option to add images from Flickr to your whiteboard screen. To add images simply click the “fr” button under “assets” to search for Creative Commons licensed images and add them to your whiteboard.

Here’s a quick overview of Scribblar that I wrote last winter:
Using Scribblar, users can collaborate on the creation and editing of images and drawings. If you have an image you can upload it to your whiteboard where you and others can edit it or comment on it. The commenting can take place directly on the whiteboard or in one of two side bar chat options. Users can chat in text or in voice.

Scribblar’s new equation editor could enable users to give short mathematics tutorials online in real-time. The new Flickr search option could be useful for editing images and creating interesting slides for multimedia presentations.

Here are some related items that may be of interest to you:
Scriblink – Your Online Collaborative Whiteboard
Scribblar – Simple, Effective, Creative Collaboration
Postica – Collaborative Sticky Notes