I'm thinking of getting a Z3660 accelerator for my recently restored #Amiga 4000, which feels a bit sluggish with its original 68040 running at 25 MHz.
I've seen one of these at #AmiWest 2024 with the Z-turn FPGA daughter board, and the owner told me it can use one of its fast ARM cores to emulate a 68040 at crazy speed.