Groupboard has reorganized and appears to be seeking some $$ for support, but it also allows the addition of a board to your own Web page. I thought I'd try to see if you could add a whiteboard and chat right inside an old Blogger blog. And it seems to work!
[May 12, 2006 - I have taken down the Groupboard, as it seemed to slow down the loading of the blog, and the ads got annoying. Hope you had a chance to look at it. It did indeed function as promised here inside the blog space! I think this would be a great addition to a blog activity, and students could take a screen shot to save their work.]
Click http://www.groupboard.com to go to the main Groupboard page, where you can link to the code that will let you add a groupboard to your own blog or Website.