With the STEMMA QT port you can attach something like this $4 RFID breakout[1] and have a badge that people can scan at a conference to get your details. No soldering needed, you can connect it directly to the board with a $1 cable and it's probably easy to program with MicroPython, although I'm not sure how extensible their "Badge OS" is.
edit: there's no MicroPython library for it apparently, but the datasheet[2] is pretty detailed. I've written Python libraries from such protocol definitions before, it's not too difficult.