Dar is a shell command that makes backup of a directory tree and files. Its features include splitting archives over several files, DVD, CD, ZIP, or floppies, compression, full or differential backups, strong encryption, proper saving and restoration of hard links, extended attributes, file forks, Door inodes, and sparse files, remote backup using pipes and external commands (such as ssh), and rearrangement of the "slices" of an existing archive. It can run commands between slices, before and after saving some defined files or directories (for a proper database backup, for example), and quickly retrieve individual files from differential and full backups. Several external GUIs exist as alternatives to its CLI interface, like kdar, DarGUI, SaraB, etc.
Email sends email to remote SMTP servers via the command line, which makes it useful in cron jobs. It will send to any RFC standard remote ESMTP server, is TLS/SSL enabled, and will allow you to encrypt, sign, and design your message on the fly. It has the capability to use signature files with dynamic options, address book functionality, and users can also attach pictures, binary files, documents, or whatever they want. It is completely compatible with GNUPG for encryption and signing, and is easy to configure and use.
EncFS is an encrypted pass-through filesystem which runs in userspace on Linux (using the FUSE kernel module). Similar in design to CFS and other pass-through filesystems, all data is encrypted and stored in the underlying filesystem. Unlike loopback filesystems, there is no predetermined or pre-allocated filesystem size.
The Enhanced File Crypt/eXtended File Stealth System (EFC/XFSS) makes your uploaded files safe on the server so that no one can read them without knowing a few details to decipher the files. It generates different obfuscated names and encrypted files so no one will know what the original format or name was.
Fiked is a fake IKE daemon that supports just enough of the standards and Cisco extensions to attack commonly found insecure Cisco PSK+XAUTH VPN setups in what could be described as a semi-MitM attack. Basically, knowing the pre-shared key, also known as shared secret or group password, the VPN gateway can be impersonated in IKE phase 1, in order to learn XAUTH user credentials in phase 2. The configuration supported by fiked is IKE aggressive mode using pre-shared keys and XAUTH. Supported algorithms are DES, 3DES, AES128, AES192, AES256, MD5, SHA1, and DH groups 1, 2, and 5. Main mode is not supported.
GNUnet is a peer-to-peer framework with focus on providing security. All peer-to-peer messages in the network are confidential and authenticated. The framework provides a transport abstraction layer and can currently encapsulate the network traffic in UDP, TCP, HTTP, HTTPS, or direct 802.11 (WLAN). GNUnet supports accounting to provide contributing nodes with better service. The services built on top of the framework include anonymous file sharing and a virtual network providing IPv4-IPv6 transition via protocol translation over the P2P network.
GPGlist is a Perl script to implement gpg encrypted alias lists in a mail server such as Sendmail or Postfix. It uses one XML config file to store information about lists. It backs up messages if an error occours, and sends out error messages to the sender of the mail. You can decide whether or not a list only accepts encrypted messages.