StartSSL™ is the trade mark of the StartCom Certification Authority - a leader of the digital certification industry. We provide you with everything from free low-assurance SSL certificates up to the most advanced PKI and security solutions for your business and personal use.

Off-the-Record (OTR) Messaging allows you to have private conversations over instant messaging by providing: encryption, authentication, deniability and perfect forward secrecy.

PhoneBook is a filesystem for Linux computers, which offers strong encryption with plausible deniability features.

StegFS is a Steganographic File System for Linux. Not only does it encrypt data, it also hides it such that it cannot be proved to exist. The data can only be read by providing a correct passphrase. It provides a set of different security levels.

eCryptfs (SourceForge page) is a POSIX-compliant enterprise-class stacked cryptographic filesystem for Linux.

The International Journal of Forensic Computer Science publishes original research and practical papers in the area of computer/digital crime and forensics. The topics of interest include Computer Law, Digital Investigation, Intrusion Prevention and Detection, Biometrics, Criminology, Cryptology, Information & Network Security, International Police Cooperation, Secure Software Development and all other related and application areas

The seccure toolset implements a selection of asymmetric algorithms based on elliptic curve cryptography (ECC). In particular it offers public key encryption / decryption, signature generation / verification and key establishment. ECC schemes offer a much better key size to security ratio than classical systems (RSA, DSA). Keys are short enough to make direct specification of keys on the command line possible (sometimes this is more convenient than the management of PGP-like key rings). seccure builds on this feature and therefore is the tool of choice whenever lightweight asymmetric cryptography -- independent of key servers, revocation certificates, the Web of Trust or even configuration files -- is required.

ssss is an implementation of Shamir's secret sharing scheme for UNIX/linux machines. It is free software, the code is licensed under the GNU GPL. ssss does both: the generation of shares for a known secret and the reconstruction of a secret using user provided shares.

Duplicity backs directories by producing encrypted tar-format volumes and uploading them to a remote or local file server. Because duplicity uses librsync, the incremental archives are space efficient and only record the parts of files that have changed since the last backup. Because duplicity uses GnuPG to encrypt and/or sign these archives, they will be safe from spying and/or modification by the server.