Please scan my towel

RFID is one of those things that seem cool until you start playing with it and then it turns out that the only uses for it are really boring. Like, you can't use it to locate stuff because the range is too short; you can't rely on stuff to have chips (food, or clothes or whatever) and it's a major time sink if you'd have to start tagging stuff yourself; it's cumbersome to install readers everywhere and not being able to rely on half lives measured in decades instead of months, etc.

I used to have an rfid chip implanted in my hand. I had all these ideas of what I was going to do with it - log on to my computer by putting an rfid reader in my keyboard, build a magic 'touch the wall and music starts playing' thing etc. All of them turned out to be very boring and useless in practice. Logging into my machine - meh, turns out that it takes longer for monitors to come back on than to type the password. Building (useful) user interfaces based on rfid is very hard and doesn't add anything over a regular proximity sensor.

The only idea I have left is that in my current house, I have a place where I could put an rfid reader so that if I'd get a chip implanted in my gluteus maximus (my butt, essentially) I could activate an automatic door opener by bumping into it when I have my hands full. I just can't motivate myself to set this up and discovering again that it's a dud in real life.

How do they prevent theft, exactly?

More accurately, to detect theft/misplacement (is it theft if I leave it on the beach?)

One interesting use:

https://vimeo.com/157990864

This library lets visitors rearrange the books organically (if you pull out multiple books on a topic, you're encouraged to put them back on the shelf together instead of finding their old homes). The books are tracked with RFID so that they remain easy to find individually.