Redditor engineers credit card sized computer that's even thinner than the plastic in your wallet

Imagine saying 'here's my card' with this.

The size of a credit card: This fully functional computer even packs an e-ink screen

The open-source Muxcard packs a functional computer, E Ink display, NFC, and wireless connectivity into a body as thin and ...
Hackaday

This Credit Card Computer Follows All Dimensions

A computer the size of a credit card is nothing new. There have been many single-board computers following the familiar dimensions. [Krauseler]’s credit card computer is different, though.
Liliputing

Adafruit’s Fruit Jam is a credit card-sized computer with a RP2350B microprocessor

The Fruit Jam is a single board computer (SBC) that’s about the size of a credit card, or a Raspberry Pi Model B. But while the latest Raspberry Pi SBCs are powered by a 2.4 GHz quad-core ARM ...