Hot answers tagged whiteboard
This seems to be pretty much perfect: http://www.twiddla.com/ It even has support for LaTeX! http://www.skrbl.com/ seems pretty good too as a slightly more basic alternative. Also, here's quite a good list of interactive whiteboard related links, many of them whiteboard webapps: http://www.shambles.net/pages/staff/intwhiteb/
You'd be looking at an online collaboration/whiteboarding tool. At a basic level, even Google Docs will do. You could also look at web services such as GoTo Meeting or WebEx.
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