Autocrypt is a set of guidelines for developers to achieve convenient end-to-end-encryption of e-mails. It specifies how e-mail programs negotiate encryption capabilities using regular e-mails.

For users, Autocrypt Level 1 offers single-click, opt-in encryption, eases encrypted group communications, and provides a way to setup encryption on multiple devices.

Turn your (old) smartphone into a Hardware Password Manager! Authorizer is Password Manager for Android with USB Keyboard emulation.

100-line Emacs Lisp program to copy passwords to clipboard and remove them after 10s from both clipboard and kill-ring.

Cryptocat is free software with a simple mission: everyone should be able to chat with their friends in privacy.

   Open source. All Cryptocat software is published transparently.
   Encrypted by default. Every message is encrypted, always.
   Forward secure. Chats are safe even if your keys are stolen.
   Multiple devices. Devices receive messages even when offline.
   File sharing. Securely share files with friends.

Available for Windows, Linux and Mac.

A GNU implementation of the Secure Shell protocols

lsh is a free implementation (in the GNU sense) of the ssh version 2 protocol, standardised by the IETF SECSH working group.

Open source (MIT licensed), available for iOS, Android, Windows, OS X and Linux.

A paper-based system for encrypting domain names into secure passwords.

Capsicum is a lightweight OS capability and sandbox framework developed at the University of Cambridge Computer Laboratory, supported by grants from Google, the the FreeBSD Foundation, and DARPA. Capsicum extends the POSIX API, providing several new OS primitives to support object-capability security on UNIX-like operating systems:

   capabilities - refined file descriptors with fine-grained rights
   capability mode - process sandboxes that deny access to global namespaces
   process descriptors - capability-centric process ID replacement
   anonymous shared memory objects - an extension to the POSIX shared memory API to support anonymous swap objects associated with file descriptors (capabilities)
   rtld-elf-cap - modified ELF run-time linker to construct sandboxed applications
   libcapsicum - library to create and use capabilities and sandboxed components
   libuserangel - library allowing sandboxed applications or components to interact with user angels, such as Power Boxes.
   chromium-capsicum - a version of Google's Chromium web browser that uses capability mode and capabilities to provide effective sandboxing of high-risk web page rendering.