I will share an experience that MAY have little to do with InfoSec and might also be flawed, but it was the best method we knew on that time. It may also include obscurity, known to be controversial.
At the school I used to go, we had a lot of problems with property (belongings) and we had to deal with them. By this, we could have anything stolen by anyone; from pencils, expensive pens, cases to backpacks and clothing. So I learned to be very careful on the unique details of any object I owned and at the same time, nobody would expect I use those details for fingerprinting. For example, wooden pencils may have small bumps; my backpack had ink spilled on a dark material, so nobody could notice that it was spilled and also it had a small piece of thread inside.
What I did was taking a timestamped photo to this details at the exact first moment I bought it with the bill containing it’s time (not for pencils but for more expensive stuff like a Parker pen), so I could show it when someone tried to take it from me.
This is obscurity, because if someone finds it, he may destroy that proof or modify it (but he still doesn’t know if it IS the detail I’m considering, as there are so many). And let’s also consider there are some native features of an object that nobody can modify or destroy unless they destroy the object.
And what happened if someone took a photo of a detail I haven’t yet seen? I had the time and moment of when I bought it that matches the bill.
And what if someone faked a bill along with the time of the photo? We could simply go to a store and check it on the system.
Details were the key.