I have developed a totally uncrackable substitution cypher. It uses 2 concentric circles of the 26 (randomly ordered) letters of the alphabet. I have challenged conventional code forums, but they merely say that a fast enough computer would crack it. This is not true. The wheels may or may not rotate after each substitution, a message of 100 characters could be hidden within say 2000 dummy characters, the recipient can read, from the message sent, where to find the the first message character, details of spacings to next message character etc etc. The most powerful computer would merely generate from 2000 code message letters every word in the English dictionary. Comments and criticism most welcome. Brave souls can ask for a coded message.