Pignus Encryption - Pignus Encryption is an encryption platform that allows users to encrypt their messages and documents.
Horde - Horde Groupware is a free, enterprise ready, browser based collaboration suite.
ProtonMail - Secure email with absolutely no compromises. Get your free encrypted email account today.
Roundcube - Web-based IMAP email client
Toolsley PGPigeon - Simple but powerful OpenPGP-compatible message encryption webapp.
Mailo - Mailo is an email client where you can send and receive emails to and from anyone with an email address.