Oh I know it’s been a thing forever. Hell, my NeXT Cube with its NeXTDimension display board was such. The NeXTDimension board ran its own entire stripped down OS. It used an Intel i860 and a Mach kernel…. It also was massively underutilized. If NeXT had did a bit more leg work and made the actual Display PS server run entirely on the board it would have been insane. But the 68K still did everything.

… I miss my NeXTs..