MirrorFolder!

FreeFileSync is a free Open Source software to synchronize files and synchronize folders available for Windows, Linux and Mac OS X. It is designed to be easy to use while having nice visual feedback along the way.

SyncToy is a free PowerToy designed by Microsoft, that provides an easy to use graphical user interface that can automatically synchronize local or network files and folders, but not WebDAV-, "Windows Mobile" files or folders and no triangle-sync as only Allway Sync, Synkron, SyncLess or GoodSync can do. No VSS-support, not portable. SyncToy can manage multiple sets of folders at the same time; it can combine files from two folders in one case, and mimic renames and deletes in another case. Unlike other applications, SyncToy actually keeps track of renames to files and will make sure those changes get carried over to the synchronized folder. »

Create Synchronicity is a nice, lightweight backup program with a very user-friendly - yet powerful - interface, that synchronizes files and folders extremely quickly (it can even recognize paths such as "MyUSB"\MyFolder, and locate the USB drive called "MyUSB").Its open source, fully portable, and multilingual ; and it can schedule backups and has many advanced options like DST correction and regexp settings.

Allway Sync is a file and folder synchronization software for Windows.

Bacula is a set of Open Source, enterprise ready, computer programs that permit you (or the system administrator) to manage backup, recovery, and verification of computer data across a network of computers of different kinds. Bacula is relatively easy to use and efficient, while offering many advanced storage management features that make it easy to find and recover lost or damaged files. In technical terms, it is an Open Source, enterprise ready, network based backup program.

LuckyBackup is an application that backs-up and/or synchronizes any directories with the power of rsync. Its main features are: backup, safety, synchronization, exclude/only include options, allows custom rsync options, remote connections, restore and dry-run operations, scheduling, profiles and command line mode.

csync is a lightweight utility to synchronize files between two directories on a system or between multiple systems.

FBackup is a free backup software for both personal and commercial use. It protects your important data by backing it up automatically to any USB/Firewire device, local or network location. The backed up data can be either compressed (using standard zip compression) or an exact copy of the original files. —but the killer feature is support for plugins that tell the backup application exactly which files to backup—an extremely useful feature for easily backing up hard-to-find files like the profile folders for browser software without resorting to manually finding each location from deep within »

We built Yintersync.NET to replicate large amounts of live data from multiple systems such as documents, databases, virtual machines and multimedia over low bandwidth connections. This is achieved by using delta encoding similar to Rsync, compression and shadow copies.

Lsyncd watches a local directory trees event monitor interface (inotify or fsevents). It aggregates and combines events for a few seconds and then spawns one (or more) process(es) to synchronize the changes. By default this is rsync. Lsyncd is thus a light-weight live mirror solution that is comparatively easy to install not requiring new filesystems or blockdevices and does not hamper local filesystem performance.

Leanware Backer is software for Windows 7, 8, 8.1 and 10 for...- Backup- Synchronization- Archiving- Transfer... of your directories and files via...- Media like USB drives, CDs and DVDs- Network- Another hard disk (internal or external)- Cable- Internet- Virtual Private Network (VPN)- Dial-up and leased lines

Synchronize folders and drives with only one click.

arRsync is a Mac OS X frontend for the utility rsync . It is intended to provide a simple interface to a powerful backup and synchronisation tool. It is quite limited but it can already performed basic backups.