Here you can download SnapRAID. Take care that it's a command line program, without any GUI interface. If you like to use a GUI, you can try Elucidate.
|Sources for Linux, Mac OS X, BSD, Solaris, OpenIndiana and any other Unix
|Binaries for Windows x64 (the most recent Windows versions)
|Binaries for Windows x86
There is also an ITALIAN manual. Thanks to Luciano Lampi.
There are also Ubuntu packages in launchpad.
If you want to show your appreciation, you can donate, or you can star it on GitHub. Donations are spent on stuffs related to SnapRAID development like to buy new hardware for my PC and internet bills.