OpenBSD/MACHINE OSREV runs on several of the older Macintosh computers.
6MB of RAM should be sufficient to boot and the system can probably
be squeezed onto a 60MB hard disk by leaving off a package or two.
To actually do much compiling or anything more interesting than
booting, at least 8MB of RAM and more disk space is recommended.
About 80MB will be necessary to install all of the OpenBSD OSREV binary
distribution (note that this does not count swap space!).  Much more
disk space is required to install the source and objects as well (about
another 105MB).

OpenBSD/mac68k OSREV now runs on most 680x0 MacIntosh's.  Specifically, it
should work on:
	68020 with 68851 PMMU and 68881 FPU
	68030 with 68882 FPU (most Macs have this)
	68040 (not including the 68LC040)

The following Macintosh models are "fully" supported.  This means that at
least the SCSI controller, ADB (keyboard and mouse), and some sort of
display will function on these models.  On some of these machines, a PMMU
and/or FPU are required if they are not provided by default with the
machine.
	Mac II, Mac IIx, Mac IIcx, Mac IIci, Mac SE/30,
	Mac IIsi, Mac IIvx, Mac IIvi, Performa 600, Centris 650,
	Color Classic, Classic II, LC520, LC550, Mac LCIII, Performa 4xx, 
	LCII, LCIII, MacTV, Quadra 610, Quadra 650, Quadra 840, Quadra
	840AV, Quadra 800, Quadra 700, Duo Series,
	Powerbook 180 and 180c, PB140, PB145, PB145B, PB160, PB170, PB165,
	PB165c


Supported devices on all of the above systems {:-include-:}:
	Internal SCSI bus and most SCSI tapes, hard drives, and CD-ROMs
	Internal sound--enough to beep on some machines, anyway
	Most NuBus video cards (there have been some
		problems with some 24-bit color cards)
	Both internal serial ports
	ADB keyboards and mice
	Ethernet cards based on the Natl. Semiconductor 8390
		(Asante, Apple, and a few others)
	Some ethernet cards based on the SONIC chip including internal
		Ethernet on many of Apple's Quadras.
	
Some systems will boot and are usable from an external terminal
(serial tty or SL/IP):
	LC475, Performa 475, Quadra 605
	possibly others

What isn't supported, but often asked about:
	PowerPC-based Macs.  They are supported by the OpenBSD/powerpc
		port.
	Machines based on Apple's IOP technology including the Mac IIfx.
	Machines based on the 68LC040 processor.  Unfortunately, the chip
		itself contains a major bug which is presently being worked
		on.  However, machines such as the Centris 605 don't work
		right now.