The included init.sh script should be installed in the root fs of your
Zipit as /sbin/init (for the BURN3 kernel), or /linuxrc if that's what
your kernel boots.

If the device /dev/mmca1, the directory /mmc, and the kernel module
/lib/modules/mmc.o all exist, the script will attempt to mount your
mmc filesystem and look for the file /etc/zipit.conf (on the card).
If this file exists (an example is included), the mmc fs will be made
your root fs and /sbin/init will be executed from the card.

If mmc booting fails, the script will attempt a nfsroot boot.  The file
/etc/nfsroot.conf (example included) is read from your mtdprefs partition.
This part is specific to Adam's software distribution.  The nfsroot script
can then setup networking and attempt to mount the nfs root fs.  If it
succeeds, some environment variables indicate to the init script the
location of the new root.

If all these attempts fail, the script will boot the internal distribution.
Also, if you mess up nfsroot.conf or something else goes wrong, holding down
the lid closed switch on the zipit during boot will bypass all of these
remote root checks and boot directly to the internal flash (a sort of safe
mode).