Burp

Burp is a cross-platform Blowfish-based file encryptor and decryptor. It is a lean, multi-platform command-line utility program that encrypts and decrypts files using a strong cryptographic algorithm named "Blowfish".

The program can use either a long sentence-like passphrase or a short (up to 16 random characters) key-string.
Unlike many similar programs, BURP writes to the output file only the cipher-text.