physics chalkboards

there is an art gallery of photographs of physics chalkboards...

http://boingboing.net/2012/11/19/photos-of-physicists-blackbo.html?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+boingboing%2FiBag+%28Boing+Boing%29

http://www.alejandroguijarro.com/ongoing/blackboards/