Areca is a file backup system that supports data compression (zip / zip64 format) and encryption, incremental backups, FTP/SFTP file transfer, delta storage mode, and many other features. It includes a transaction mechanism, which guarantees the integrity of your backups. Two user interfaces are available: a command-line interface (useful for backup automation) and a graphical user interface (useful for backup administration).
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.
rdiff-backup backs up one directory to another. The target directory ends up a copy of the source directory, but extra reverse diffs are stored in a special directory so you can still recover files lost some time ago. The idea is to combine the best features of a mirror and an incremental backup. rdiff-backup can also operate in a bandwidth- efficient manner over a pipe, like rsync. Thus you can use rdiff-backup and ssh to securely back up to a remote location, and only the differences will be transmitted. It can also handle symlinks, device files, permissions, ownership, etc., so it can be used on the entire file system.
ISO Master is an easy to use GUI CD image editor for Linux, BSD, and Windows. Basically, you can use this program to extract files from an ISO, add files to an ISO, and create bootable ISOs, all in a graphical user interface. It can open both ISO and NRG files, but can only save as ISO. It is based on bkisofs, a library for reading, modifying, and writing ISO images.
scdbackup is a simplified CD/DVD backup program for Linux. It can back up large amounts of data on one or more media, with no special tools needed for reading the backup. It supports ISO9660 filesystems and afio archives. Its special features are automatic division of data into multiple volumes, verification of write success, incremental backups, a search and restore helper for large ISO9660 backups. CDs get written via cdrecord, wodim, cdrskin, or xorriso. DVDs and BDs get written via growisofs, cdrskin, or xorriso.
PBZIP2 is a parallel implementation of the bzip2 block-sorting file compressor that uses pthreads and achieves near-linear speedup on SMP machines. The output of this version is fully compatible with bzip2 1.0.2 or newer (ie: anything compressed with PBZIP2 can be decompressed with bzip2).
Rsyncrypto allows you to encrypt a file or a directory structure such that they can later be synchronized to another machine using rsync. This means that local changes to the plain text file result in local changes to the cipher text file. rsyncrypto compresses the plain text file prior to encrypting it with gzip using the "rsyncable" patch, which is available from the rsync sources.
changedfiles is a framework for filesystem replication, security monitoring, and/or automatic file transformations--essentially any application where you'd poll files or directories and either do something to them or send them somewhere else (or both). The difference is that the kernel tells you when they change instead of you having to poll. It's an easy real time FTP push mirror to one or multiple sites. It's also a full fledged MySQL client, so you can do realtime database operations (for example, batch imports). It consists of two parts: a kernel module (works with Linux kernel version 2.4) which reports to a device whenever a file on the filesystem changes, and a daemon which runs in user space and can be configured to do almost any action when a change to a file matching the one of the patterns it looks for is reported. The kernel module is SMP safe and has been tested on Intel, PowerPC, and Alpha.