Attic is a deduplicating backup program. The main goal of attic is to provide an efficient and secure way to back up data. The data deduplication technique used makes Attic suitable for daily backups since only actual changes are stored. Main features: space efficient storage, optional data encryption, and off-site backups.
(Qt)-Backstep.py is commandline and graphical (Qt) backup software written in pure Python. It can back up any directory to CD-R(W), DVD-R(W), USB key, or another directory. It is a continuous backup solution. It works like a time machine. It contains a backup network server. It can send backups over the Internet or your network.
Backshift is a deduplicating (variable-sized, content-based blocks), compressing (xz or bz2) backup program. Full saves and incrementals are pretty indistinct other than the amount of data transmitted, somewhat like with "rsync --link-dest" but without the huge number of hardlinks. It also de-duplicates large file content at a granularity of about 2 megabytes on average; there tends to be a unique copy of each file with size less than around 2 megabytes on average.
S3QL is a file system that stores all its data online. It supports Amazon S3, Google Storage, and OpenStack and effectively provides you with a hard disk of dynamic, infinite capacity that can be accessed from any computer with Internet access. S3QL provides a standard, full featured Unix file system that is conceptually indistinguishable from any local file system. Additional features include compression, encryption, data de-duplication, immutable trees, and snapshotting, which make it especially suitable for online backup and archiving. The design favors simplicity and elegance over performance and feature-creep. Care has been taken to make the source code as readable and serviceable as possible. Solid error detection, error handling, and extensive automated test cases are provided.
dupli.back is a backup tool built around the Duplicity backup engine. It's designed to enable users to easily create and manage backups on removable media such as external USB hard disks. It supports not only reverting whole backups to particular moments in time, but supports reverting selected individual files to moments in time. It also supports exporting backups to tgz files.