I have a Minisforum UM690S, it's about the same size (5x5x2.25 inches) and works well as a small machine. They just announced the EliteMini AI370 today that has the latest AMD laptop chip with 12 cores/24 threads - I assume that would also be a decent linux server (note that ram is soldered on that one).
Just ordered one the UM690S after this comment - I had been looking for another machine like it and saw the sale. Thanks for sharing!
I just deployed another System76 machine that I’m using for the same purpose — using both for redundant containerized web servers I’m self hosting. I got it with 64GB RAM.