GnuPG - GnuPG is a complete and free implementation of the OpenPGP standard as defined by RFC4880 (also known as PGP).
BoxCryptor - Boxcryptor encrypts your sensitive files before uploading them to cloud storage services like Dropbox, Google Drive, Microsoft OneDrive, Box, and many others.
GPG Suite - Use GPG Suite to encrypt, decrypt, sign and verify files or messages.
CrococryptMirror - Encryption tool for mirroring directories to encrypted containers
Autocrypt - Convenient End-to-End Encryption for E-Mail
LibreCrypt - LibreCrypt (formerly DoxBox) is an open-source disk encryption for Windows and the successor of...