Sometimes I look at the ordinary things and just see Raspberry Pi inside. Of course, in real life, there is no Pi inside, so I need to build it in there myself. Recently I found a minimalist wallet (or badge) and transformed it into an eInk CyberBadge!
To me, the wallet looked like a perfect sci-fi themed frame for an eInk display. Resulting in some kind of smart badge.
In this case, even Pi-zero is too much, so I was looking for ESP32 based bord. Badgy could be the option, but unfortunately, it is out of stock for a long time. Good thing I've discovered LILYGO® TTGO T5 series. V2.8 model would be too big (require some frame cutting or (un)soldering), but V2.3 fits just right! Even some space left for the battery.
Original wallets back panel are unscrewable by a 1.5mm t5 screwdriver and enclose LILYGO® TTGO T5 V2.3 and 290mh battery perfectly. For a front panel, I've cut a screen-shaped hole in a credit card (wallet originally intended to hold credit cards), then glued it with a carbon film to look nicer. See:
Also, the wallet has openings on both sides, allowing access the on/off switch (with a screwdriver) and USB port (if you have a really flat cable).
Note that the screen is monochrome, not grayscale (no greyish mid-tones like you might have seen on Kindle). It has only 2 colors, so I need to get pixel-perfect black-and-white images. To get a nice looking monochrome photo I went on pipeline: remove.bg→Ajust levels in Krita→ditherpunk→Img2Code.
As a bonus let me share some pixel perfect-images, if you want some design:
Q: Why do you need that?
A: I don't know. My conference speaking days are over, and will there be any conferences at all? It was just a cool thing to build, that's all.
A: You know, sci-fi movies promised us cool devices like Multi-Pass. But all we've got are boring glass rectangles with no character. So I need to have some cool stuff from that alternate timeline :)