I love how these cards work in Japan. There’s a bunch of different operators but they all work across the country – for example, if you buy a KITACA in Sapporo, you can use it in Tokyo and Osaka and anywhere else. And of course you can use them in a bunch of places, from all the transit options to vending machines and coin lockers on stations to konbini everywhere and even some restaurants.

(Of course it’s a bit more complicated: https://commons.wikimedia.org/wiki/File:ICCard_Connection_en... – but still impressive nonetheless!)