New encryption block...

[Era Scarecrow via Digitalmars-d]

  Something coming to mind is the idea of making a small algorithm 
to be used with other already existing encryption functions to 
extend the blocksize of encryption with minimal complexity 
growth. In theory this would extend a blocksize of 4 or 8 bytes, 
to say 64 bytes. Not only that each stage could use a different 
encryption type (or all the same).

  let's assume a very small blocksize of 2 bytes, and extend it to 
8. So logically it could be (numbers refer to original offsets):

  12 34
  56 78

  Each block (4) is encrypted normally. Then it's rearranged to 
say:

  35 28
  71 64

  Then encrypted again. Preferably a the rearranging is complex 
enough to do several steps before calling it done.

  Lastly there could be an optional salt block. Such a block would 
allow multiple instances/results of the same encrypted data and 
plenty of dummy data too, helping to hide identically encrypted 
data up to the combinations of the size of the salt.