HashTab provides OS extensions to calculate file hashes and supports many hash algorithms such as MD5, SHA1, SHA2, RipeMD, HAVAL and Whirlpool. As Windows desktop software HashTab runs as a Windows shell extension and on the Mac it is implemented as a Finder plugin. HashTab provides an easy way to verify file integrity and authenticity.

dnscrypt-proxy provides local service which can be used directly as your local resolver or as a DNS forwarder, encrypting and authenticating requests using the DNSCrypt protocol and passing them to an upstream server.

The DNSCrypt protocol uses high-speed high-security elliptic-curve cryptography and is very similar to DNSCurve, but focuses on securing communications between a client and its first-level resolver.

While not providing end-to-end security, it protects the local network, which is often the weakest point of the chain, against man-in-the-middle attacks. It also provides some confidentiality to DNS queries.

Explications intéressantes sur le format de stockage des clefs SSH générées par OpenSSL et sur le moyen d'améliorer l'algo de chiffrement utilisé pour chiffrer les clefs privées.

Some thoughts on best practices for OpenPGP keys