Online whiteboard - free

This is an online whiteboard that you can invite others to via IM or email and then use as part of a collaborative process. You can then send a copy of the whiteboard to an email address
http://www.imaginationcubed.com/LaunchPage
I can imagine it being of use in conjunction with Skype.
Beauty, we have just about eliminated Centra with some free smaller tools. I don't think I will need any special training to use it either ;-)