Many introductory courses to cryptology and computer security start with or include a discussion of classical ciphers that usually contemplates some cryptanalysis techniques used to break them. Ganzua (picklock in Spanish) is an application designed to assist the cryptanalysis of ciphertext obtained with monoalphabetic or polyalphabetic ciphers. It can use almost arbitrary character sets for the plain and cipher alphabets as well as obtain the standard relative frequencies of many languages and provide other useful data.