Just stumbled across
this thing, which is not actually an Ethernet hub -- it's 8 RJ45 RS-232 ports intended to be driven over SCSI. (Already warned the vendor, so they might move it to another category shortly. It's a Central Data ST-1800 for $4, if they do.)
The programming interface probably isn't too complex, though I have no idea where you'd get documentation. I also haven't bothered figuring out what their idea of 'normal' vs. 'high performance' really means.
But at these prices in the surplus market, perhaps supporting some sort of hardware
like this would be a fun project for someone?
Edit: docs here, looks like 57600 is the peak rate for the 'normal' ones, so maybe it's not horribly exciting.
