ChoiDujour 
Converts Nintendo Switch firmware update packages to installable images/files that can be transferred to the device itself.
Usage
ChoiDujour.exe --help for a detailed Usage description page.
Generally you can just drop the desired source firmware update package onto the exe as well, it will output NX-X.X.X folder on success.
Binary releases available at https://switchtools.sshnuke.net
Responsibility
I am not responsible for anything, including dead switches, blown up PCs, loss of life, or total nuclear annihilation.