Mac firmware has a special boot mode that allows you to offer its internal hdd to another computer as an external disk (you just connect the two machines via an IEEE 1394 cable). Only the second machine needs a functioning OS installed.
Any good suggestions for something similar on the PC side of things? Block level access isn't important to me, I'd just like to be able to copy files off it. It doesn't matter to me if it uses Ethernet, IEEE 1394, or wifi - I just like having a quick way to access files on a client PC.
Is there any single-purpose Linux distro specially designed to do this? It'd be nice to have something super simple, quickbooting, and small that I could install on a USB drive. I used to use Knoppix, but it's overkill as a Target Mode replacement.