Since I did so 2-3 weeks ago, I've erased my boards completely three times over. Instead of taking notes from my meetings with each student and giving him or her a copy, I use the boards, and delegate the responsibility to the student receiving instructions or suggestions. It's generally worked out quite well, with some slight latency.
In other news: scottharmon had his first of three depth orals today, a presentation on computer security. I'd normally try to attend such things, but I found out only about 3 hours before the event, and could only forward the announcement to my students and my colleague Simon Ou, whose research area is security. I'll see about getting the announcement pipeline a little better-oiled for next time.