I've just made a custom KNOOPIX (690Mo) aimed at French speaking users. It's name is Ocaml FR KNOPPIX.
knoppix lang=fr is the defaut boot option thanks to knoppix-customize which is a very convenient way to customize boot.img.
It's available at http://mpsi.leledy.org.
The very few docs are in French.
The market is French students in computer science who have to learn Ocaml.
Also a special effort was made to have modern TeX producing high quality PDF documents in French (accents) which is not trivial.
I had only partial success in getting control of /home/knoppix : not all /etc/skel (e.g .emacs) are copied in it at boot time. But I did manage to have my own app (emacs) started on the desktop by mean of .kde/share/config/ksmserverrc in /etc/skel.
Also noticeable, I had only USB keyboard (from Apple Macintosh !, not for PC) and it was not so a problem: sometimes the boot process stops while probing USB, but booting again solves tgis issue. Strange enough, original KNOOPIX cd doesn't boot any more with this config but my own CDs do boot !
I made my customization by booting with the system being customized and with the chroot mechanism described in HOWTOs. In this case I found convenient to use X11, and found a simple way to do X11 while chrooted: DISPLAY=:0.0 doesn't work but DISPLAY=localhost:0.0 works fine if you don' forget to do xhost + localhost in the base environment.
Salutations
SanDisk 128GB Ultra Fit USB 3.2 Flash Drive, Black - SDCZ430-128G-G46
$11.99
SanDisk 512GB Ultra Drive Dual Go USB Type-C Flash Drive Green SDDDC3-512G-G46G
$49.99
High Speed Metal 64 GB USB 3.0 Flash Drive Pen drive Memory Disk 1 year Warent
$19.99
SanDisk 16GB Ultra USB 3.0 Flash Drive - SDCZ48-016G-U46
$6.25
Jumpdrive S80 32GB USB 3.1 Flash Drive, up to 130Mb/S Read (LJDS080032G-BNBNU),
$14.58
Lenovo USB 16TB 3.0 USB Flash Drive Thumb Disk Silver Transfer Metal Memory
$24.99
Mechanical Style Flash Drive USB 3.0 High Speed 16TB Large Capacity Waterproof
$8.37
2TB USB 3.0 Flash Drive Memory Photo Stick for iPhone Android iPad Type C 3 IN1
$16.72
USB Flash Drive Memory Stick Pendrive Thumb Drive 4GB, 8GB, 32GB, 64GB 128GB LOT
$249.37
SanDisk Cruzer Glide USB 3.0 16GB 32GB 64GB 128GB 256GB Flash Drive Memory Lot
$276.48