I was looking through a very old thread about this topic and link that was posted there led to a company making some pretty interesting looking products. This one in particular caught my attention:
http://www.2ndwave.com/details.asp?ProductID=42&mscssid=KAQBX0TA1M8F8LQJ5RBDNL9LCKCL8200
This device allows you to use SCSI devices on a USB Mac. The thing that makes it interesting to me, is that the communication must be bi-directional. If the communication is bi-directional, would it be possible to plug this into the external SCSI port on an older Mac via a gender changer and use USB devices??
The SCSI/USB adapter works as a USB client device and is unlikely to contain a host controller chip. Even if it did, the Mac would require drivers to control the host.
That's entirely correct.
We've had the same discussion about USB->PS/2 and USB->serial adapters.
You can go one way, but never the other.
Nevertheless, you just might be able to connect a Powerbook to the SCSI end, boot it in SCSI Disk Mode and see the internal disk from another Mac as a USB drive. Maybe.