Thanks to Ian Hanschen for tweeting information about a project called the RaSCSI:
http://retropc.net/gimons/rascsi/
This device connects a Raspberry Pi via the 40pin GPO header to a SCSI connector, and with matching software enables the Raspberry Pi to emulate multiple SCSI devices, including hard disks and CD-ROMs. Currently the project is aimed at the Sharp X68000 personal computer, a Motorola 68K based computer that existed in Japan in the late 80s and early 90s, known for its excellent quality home ports of popular arcade games.
However the author notes that it can be used as a simple SCSI device on the FM Towns (a Japanese 386/486 based personal computer) as well, and as Ian mentions, there’s quite a lot of potential for the device to be extended in functionality to any computer or arcade system that required SCSI devices to operate.
Currently devices like the SD2SCSI exist as an SCSI hard disk and CD-ROM replacement option (popular with Capcom CPS3 arcade users as well as older PC and microcomputer enthusiasts to replace the SCSI-CD-ROM with a more reliable optical drive emulator), but enabling SCSI emulation to be performed in software on a cheaper Raspberry Pi board offers quite a lot of potential.
It would be fantastic to see efforts to bring this to a number of other SCSI based systems. Thanks to Ian Hanschen for his original tweet:
Reminder that X68000 has an awesome SCSI hard drive replacement that we need to bring to other machines. Target emulation via Raspberry Pi, allowing you mount arbitrary disk images, ISOs, the Pi FS, and access the network (using a SCSI Ethernet driver). https://t.co/fF8dXYugbT
— Ian Hanschen BLM (@furan) September 19, 2020