oh, and battery powered (I have two of these) external 68-pin portable CD-ROM modules (1 is 8x the other is 20x) from Panasonic. I can also use it as a stand-alone CD-ROM. I have gotten my PowerBook 540c to boot from it. Uses 4 AA batteries, or a rechargable Li-Ion battery pack.
I also have a battery-powered Parallel/SCSI CD-ROM. It's 2x, and has a SCSI port, but there's a SCSI->Parallel (Centronics) adapter you can hook it up to a PC with a Parallel port as an external drive. Works great for DOS. But you can't boot from it.
I also have a battery-powered Parallel/SCSI CD-ROM. It's 2x, and has a SCSI port, but there's a SCSI->Parallel (Centronics) adapter you can hook it up to a PC with a Parallel port as an external drive. Works great for DOS. But you can't boot from it.