I found a link to pWhiteboard. I uses Mysql and PHP. May be a nice module for Moodle:
pWhiteboard is open source, and Free software, released under the Gnu GPL
Well, really this is just a text field that everyone can edit ... Wikis are probably much better ways to do this.
A real whiteboard lets you scribble on the page .. eg http://drawboard.sourceforge.net/
A real whiteboard lets you scribble on the page .. eg http://drawboard.sourceforge.net/