Kirk McElhearn pulled together a list of things you might want to track with an AirTag. While some might feel obvious, this is worth a scan, just to wrap your head around what’s possible, get you thinking about your own situation.
One thing on the list I did not think of is leaving an AirTag in my car. There’s theft tracking, which is not an Apple recommended use, but there’s finding your car in a crowded parking lot. I’m definitely in on that use case.