Tarsnap is a secure online backup service for BSD, Linux, OS X, Solaris, Cygwin, and can probably be compiled on many other UNIX-like operating systems. The tarsnap client code provides a flexible and powerful command-line interface which can be used directly or via shell scripts. At the present time, tarsnap does not support Windows (except via Cygwin) and does not have a graphical user interface. - Matteo Scotuzzi