Make a bootable USB flash drive with FreeDOS

We live in an imperfect world, in case you didn't know. Due to various social factors, at the time of this writing (2013), we were still flashing motherboard firmware (BIOS) updates using MS-DOS. Now, getting MS-DOS onto a flash drive is something of an art form. [SIGH]

NEWS FLASH: Since the Balder image uses FAT16 instead of FAT32, and since the HP USB format tool insists on creating a single partition spanning the entire disk, the procedure below only works for 4GB and smaller flash drives. If you have, say, an 8GB or 16GB (or bigger) drive, you'll have to modify the procedure. Luckily, the modification is not difficult -- in fact, it's easier than the original procedure. Instead of the Balder image, use the Windows 98 files located in the ZIP archive win98boot.zip (available on-line).

Procedure for small flash drives (< 4GB, but the smaller the better)

1. get balder10.img from http://www.finnix.org/Balder
2. Mount the floppy image via the loop device: $ mount -o loop balder10.img /mnt (for more information, see $ man mount
3. copy the files from /mnt to a Windows box (using Samba or Sneakernet)
4. over on the Windows box, run HP USB Disk Storage Format Tool (also known as the HP Drive Key Boot Utility?) - downloadable in a million billion places, just run a search for it
5. in that stinky Windows application, choose "Create a DOS startup disk - using DOS system files located at:" and point it to the files you copied over from /mnt
6. also check the "Quick format" option; otherwise the format will take forever for a larger drive
7. press "Start" button and wait for the app to do its work
8. at some point, the flash disk will appear (in Windows) just like any other disk – you can open it in, e.g., Windows Explorer
   
9. copy the rest of the balder10.img files over to the flash disk (the DOS system files were already copied in an earlier step)
10. copy over whatever else is needed (BIOS flash files, etc.)
11. unmount (safely remove) the flash disk
12. boot the target machine from the flash disk