The other two items are considerably subtler. There are four commemorative lapel pins ($4.50 each) that you can load with prepaid funds, and a flexible NFC sticker that you can attach to all kinds of objects and accepts prepaid values as high as $180.

If you want any of them, you'll probably have to wait until you're visiting the country. Visa is currently selling all three through South Korea's Lotte Card (both online and in customer centers), and they'll otherwise be available through Olympic Superstores. Really, these are technology demos that just happen to be useful in other parts of the world. And that's a bit of a shame -- people in many colder climates would likely appreciate those gloves.