Not sure who was first(as the article linked isn't dated), but remember seeing something a few years back that someone else created as a business Linux card
Edit: somehow I duplicate posted when I edited my last comment, qchris beat me to posting this (and was on HN in 2019, I think I probably saw it on hackaday at the time)
I'm the author of the first article. I'm very pleased to see a trend of this theme!
Of course, the software on this card is perhaps more impressive than mine. All I did was patch the kernel and make an image. This card does all that and emulate a processor.
I was greatly entertained by the description of the DMA. I am unsure why DMA always ends up being the boogeyman, but I don't disagree.
"Booting up" [suspicious device] isn't really a security risk. It's it's own hardware with no access to anything else you own.
Plugging it into your PC, which this one seems to almost require, is the dangerous part of course, but not any more so than plugging in any other USB device. The fact this runs Linux is essentially irrelevant. A promotional USB stick, charging cable, battery bank or whatever other USB gadgets marketing departments throw around these days could hurt you just as easily.
An interesting application of this could be to share your PGP/whatever public key. Anything providing storage would work but maybe so would a full computer.
Tracked it down: https://hackaday.com/2019/12/24/now-even-your-business-card-...
https://www.thirtythreeforty.net/posts/2019/12/my-business-c...
This design looks better.
Both creative
Edit: somehow I duplicate posted when I edited my last comment, qchris beat me to posting this (and was on HN in 2019, I think I probably saw it on hackaday at the time)