I just thought I would mention this, since I have not seen it listed here. 

With the advent of Mac OS X Apple has written a new bootloader, BootX,
which has bunch of capabilities, including booting ELF kernels, "UFS" (for
some variants of UFS ;-) booting, etc. I don't know if it sets up the MMU
and stuff appropriately for NetBSD, but it would be nice to see NetBSD
work with it.

More importantly, as part of this a whole bunch of machines have had
updated OF patches made to make them boot more reliably, including many
machines not supported by OS X. They are available in the Darwin
Repository as part of the nvram command (part of the system_cmds module I
think) Patches exist for:

Hooper
Kanga
PowerSurge
PowerExpress
Alchemy
Gossamer
Silk
Mainstreet
Wallstreet

Hope some of you find these useful.

Louis
---------
Louis Gerbarg
Darwin Developer