What's amazing is precisely the fact that you can plug a USB stick or CDROM or even a floppy (if you encounter a computer still equipped with one) and boot a computer using your own operating system instead of the one installed on it. It's a very valuable trick, not least in Ainz's situation in which he needed to recover data from a dead computer.

It's not really unprecedented, though. Many flavors of Linux are available in the form of a bootable DVD, or a USB flash drive. Puppy has to win the award for smallest Linux, I'd say. Also, the trick's been done to Windows, with a utility (forget the name, dammit) that extracts its DOS underbelly to create a disk that will boot to the DOS command line. Which, again, sounds primitive, but it's a lifesaver when you need to get inside a busted machine.

Or you need to break into a computer. It hardly matters if you protect Windows with a password, when somebody can come along and just bypass Windows. Linux can read a Windows hard drive just fine, thank you. When you log into your Linux as "root", you become the Windows administrator too, with all the rights, privileges, and power appertaining thereto.