hell yeah, I've made a whole useless product like that! In lab, we had OLED display powered by NFC too, and touchscreen e-ink tetris device, and spot welder lol. Nobody believed me it's possible, even engineers who worked with me, might be I was the first one to come up with this hack.

This is how tap to pay cards work IIRC. Secure storage chip, transceiver chip, NFC coil, boom