caesarcrack is a native (C++) program which analyzes a ciphertext for character frequency distribution; given the distribution, computes the shift register of the caesian cipher.  Take for example:  "what we wish, we readily believe, and what we ourselves think, we imagine others think also."  If we apply a shift-register to the alphabet of the above quotation, we get the following ceasian cipher text:  "BMFY BJ BNXM, BJ WJFINQD GJQNJAJ, FSI BMFY BJ TZWXJQAJX YMNSP, BJ NRFLNSJ TYMJWX YMNSP FQXT."  caesarcrack can take in this text as a plaintext file, without knowing the shift-register, as well as the given alphabet (a-z) and will analyse it for the frequency distributions of each character using Chi Squared Distribution and determine the shift register of the ciphertext as well as output the decode plaintext.