The technique's called: The Steel Finger.

I grew tired of all the lame "crypto" challenges out there, which basically throw some random obfuscated text at you with the request to "decode the message". In case you didn't realize, this has nothing to do with cryptanalysis, it's just nonsense. On the other hand, you have stuff like data's challenges in the neworder newsletter, which are literally impossible to solve without solid mathematical background knowledge. Thus, I decided to give you something which an average coder can solve, but which is also educational and forces you to research some early basics of cryptanalysis.
  1. vigenere chiffre
  2. linear transformation ciphers
© kthx.