Shouldn't be too hard to turn something like this into a Nostr Signing Device https://www.lilygo.cc/products/t-dongle-s3
I did it!! https://image.nostr.build/f79d852670e1c640ab0d19eb1cc052aeec473f1c99574088494b414e7ef40903.jpg
Hell yeah. I'm so jealous its going to be a least a week before they ship the one I ordered. Dose it work with https://next.nostrudel.ninja/#/signin
Before, it was not. But now it's work!! I have update code in my repository https://github.com/AlbiziaLebbeck/nostr-signing-device . It's fork from lnbits.
So tiny! Put it up for sale on Shopstr :)
That's a fun formfactor for an ESP32. I want one just to tinker with. And $10!
It's okay. Just no display.