into n blocks of every 1st, 2nd, … char 3. For each, find the byte that gives best result 4. Stick those bytes together for the key! Works best for text with a key >1 byte long
code for this example: https://github.com/technoskald/xorthis Started this week: https://class.coursera.org/crypto-008/class Matasano Crypto Challenges: http://www.matasano.com/articles/crypto-challenges/