I was an architect on the Anton 2 and 3 machines - the systolic arrays that computed pairwise interactions were a significant component of the chips, but there were also an enormous number of fairly normal looking general-purpose (32-bit / 4-way SIMD) processor cores that we just programmed with C++.

I spent a lot of time on systolic arrays to compute crypto currency POW (Blake 2 specifically). It’s an interesting problem and I learned a lot but made no progress. I’ve often wondered if anyone has done the same?

Not really. I work for NextSilicon. It's a data-flow oriented design. We will eventually have more details available that gradually explain this.