I wonder what you could build as a retro-inspired home computer based on something like the STM32H7S7? You'd need external memory and PSRAM, but I suspect you could get something amazing out of it. 600MHz, HW graphics (1024x768), audio (I2S), FD-CAN (a fun extension bus), 10/100 Ethernet, even SPDIF. They're around $10/each in small quantities. It's not a full microprocessor (no MMU), but it's going to be wildly more powerful than something like the Acorn Archimedes (12MHz).