I asked on twitter for online whiteboard solutions. These are some of the
ones that were suggested. There's a few that I managed to check out
quickly and got rid of the links without thinking that I might want
them for posterity. This is what I had left. Know of others? Please
add in comments.

http://smartkapp.com/en/products/kapp?gclid=CKWCvvi8hMgCFQuLaQodAU0KnQ 
https://awwapp.com
https://realtimeboard.com
http://webwhiteboard.com/#/
https://www.scribblar.com
http://www.groupmap.com
https://precursorapp.com
https://mural.ly
https://spacedeck.com