Shoebill is an all-new, BSD-licensed Macintosh II emulator designed from the ground up with the singular goal of running A/UX.
A/UX 1.1.1 through 3.0.0 (but not 3.0.1 or higher, yet)
Shoebill requires a OS X, a Macintosh II, IIx or IIcx ROM, and a disk image with A/UX installed.