Check out this great open hardware project created by a student at the University of Naples Parthenope that behaves as a great door data display for crucial information. (NOTE: description is in Italian.)
The purpose of the label is to display real-time information such as: number of the study, teacher/s, office hours, contacts, mail and/or telephone numbers etc etc … but above all alerts taken in real time by one of the communication channels of the university.

Printable catalog (PDF)
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