As my graduating students pack up and move out, they have been finding things. My things.
In some ways, I am a very organized person. Most of these ways involve getting things done and not forgetting (too often) when I have something to accomplish by a certain date. In other ways, I am not an organized person. Most of those ways involve the arrangement of my office and the things in it.
Although much of the scientific literature is available in electronic form these days, some things are not. I lend books and back issues of journals -- as well as assorted other tangible objects -- to my graduate students. And I am not good at keeping track of who has what.
Yes, I have tried check-out lists, but after the first few entries, the lists tend to sit there, unused for both check-out and return. And even if I were diligent about enforcing the sign-out/sign-in system, sometimes students borrow things when I am not around, or one student borrows something and then lends it to someone else. The lists are never accurate, so I have given up on them.
If I can't find something and I'm pretty sure it's not in my office, I just send an email around to the group and say "Does anyone have X?" and either it turns up or it doesn't.
Something interesting about the most recent finding and returning of things by my departing graduate students is that one of them had items borrowed by a student who graduated 4-5 years ago and had given the borrowed items to this other student (his housemate), telling him to give them to me. But he did not give them to me. He forgot he had these things until he graduated and started packing up his office and home. Recently I have been reunited with some very long-lost items.
I have had an unusual number of students graduate this spring/summer, so lately I have been getting a lot of books and other items returned to me. Somehow in the intervening years while these items were in other offices, the space they formerly occupied got filled in with other things, causing me to contemplate in a very serious way the possibility of considering maybe doing some major office organizing this summer.
If I do organize my office, I doubt if this effort will be accompanied by the creation of a system for organizing the lending of books etc., but at least I will be starting almost from scratch, with only a few (?) things already lent to current students and postdocs.