Replied as a sibling, and it certainly doesn't qualify as useful, but Dmitry Grinberg wrote an ARM emulator for AVR, soldered a SIMM to a board with an ATMEGA12

Replied as a sibling, and it certainly doesn't qualify as useful, but Dmitry Grinberg wrote an ARM emulator for AVR, soldered a SIMM to a board with an ATMEGA1284P and an SD card on an SPI bus connection, and got Linux to boot. The 24MHz clock rate is effectively reduced to about 6.5kHz, but it might be possible to find a use for such a device.