Crypt4Free

crypt4free is a free tool for file encryption that uses two industrial algorithms that are considered standard (DESX with 128 bits and Blowfish with 448 bits) to protect files.

The user will indicate a password by which crypt4free will restrict access to the file and without which it is not possible to see its contents.

Other supported functions of crypt4free are:

Encrypt/decrypt ZIP archives and navigate their contents; and the elimination of files in such a way that they cannot be recovered.

Truecrypt and Filewaster are two other tools for encrypting giles that you should also check out.