Combination Lock Boxes

from blog Jeff Kaufman's Writing, | ↗ original
Traditionally we control access to our houses with "something you have": a key. This works pretty well, until you have a visitor arrive when you're not home to give them a key. The traditional way to handle this is to hide a key (under the mat, in a flower pot, etc), turning this into "something you know" (the information about where the key is...