I'm soon (next few weeks) going to be bringing up an A/UX system running on a Mac Quadra 800.
A/UX was Apple's first Unix operating system for the Mac, and ran on Motorola 68030 and 040 processors - The Mac II and Quadra series. It's a System V R2.2 kernel with BSD and SVR3 extensions, including TCP/IP and Streams. It is probably one of the most elegant and stable, true Unix systems ever built.
Physically, it will be running on a Quadra 800: 68040 33MHz, 68MB RAM, SCSI with a couple of disks, a CDROM, and an Archive DAT tape drive.
Getting this system up and running will get me very close to completing my collection of running AT&T Unix systems. I'll have Seventh Edition, SVR2, and SVR4. The only thing I'll need after that will be a SVR3 system: Microport or Interactive would be perfect. If anyone has a copy they'd like to donate to the cause, it would be very much appreciated!