S.S.E. File Encryptor - S.S.E. File Encryptor is a cross-platform encrypter/decrypter of files and folders.
CrococryptFile - Strong file encryption tool
GPG Suite - Use GPG Suite to encrypt, decrypt, sign and verify files or messages.
GnuPG - GnuPG is a complete and free implementation of the OpenPGP standard as defined by RFC4880 (also known as PGP).
Autocrypt - Convenient End-to-End Encryption for E-Mail
Chatlink.com - Anonymous communication platform