Sigh. What were the odds of the HD on my month-old MacBook Pro and the HD on my somewhat older one (which was filling in for the moment as a backup) failing on the same night? Pretty low, I'm guessing, but that's what has happened. The Genius Bar has confirmed that the new drive is completely toast, and Apple is replacing it now, but of course they can't salvage the data. As for the old drive, while it won't boot and isn't visible to other machines in target disk mode, I am able to mount it in single-user mode and even view text files. What I can't seem to do is mount my external FireWire/USB2 drive so that I can try actually copying the files off.
I've re-read the man page for "mount" in hopes of discovering the correct incantation, but so far it has eluded me. I've been trying things like "/sbin/mount -w /dev/disk1 /Volumes" and "/sbin/mount -w /dev/disk1 /Volumes/rescue", which return "Permission denied" and "No such file or directory" respectively...not sure that's the right device, but finding an acceptable mount point seems to be an issue regardless. Hoping someone can point me in the right direction, and thanks for reading.
MacBook Pro,
Mac OS X (10.5.8)