I checked the Bestcrypt site and found they have an old version (which is now free) for use with DOS/Win3.1x.
Check out: http://www.jetico.com/index.htm#/bcrypt.htm
and the download page as well...
You have to do your encryption/decryption under DOS, therefore I foind it a bit limited. If you are working under win9x/nt/2k, and and have your data ready for encryption, you would rather prepare your container file and dump the data in the environment you usually work (w9x/nt/2k).
It will be foolish to boot into DOS, access your data, and then dump the data into the encrypted container in DOS. But then that's me... Since the utility is free for DOS, I guess it is something handy.
I am not sure if the container file you create will understand any filesystem other than FAT16 though...
Once your data files are in the container (which is basically a big 600+ mb file), then burn the file to your cd in your OS. You can make your cd bootable so that will not affect the container file, and may be put in the DOS modules for the BestCrypt, so that when you access your CD under DOS, you can mount and open the container file!
The main problem I see is that quite many of your data will be generated with new Apps, so it may be limited use to be able to access them under DOS, since you may not be able to work or even read the data files (unless they are RTF, TXT, etc standard format files)!
For what it's worth, if anybody feels like testing it, the software is there.
Scramdisk is now called drivecrypt, and commercial. Worse it is only for Windows platform... no DOS version...
So strike that out!