On: Detecting unauthorized physical access with beans,...

[zeristor]

At primary school we had a lid as a desk, and I used to place rulers and a protractor in a certain combination that would be dislodged if open.

OK it could probably be reproduced, and I don’t think I recorded what the position was, but I was only 10 at the time.

[xpe → zeristor]

Sounds like a fun 3D bin-packing algorithm.