I put tags (not ff) on all my carry ons. I also have an address tag and office phone number on my laptop, which was helpful when the person behind me at security at an airport - had an identical computer.

Several years ago, I got a handicap permit (the kind that hang on the rear view mirror) to take my invalid mother around. I lost it at either the doctor's office or supermarket. Some kind hearted soul found it, saw my address tag, and returned it to me.