Unison is a file-synchronization tool for Unix and Windows. See the manual for a detailed look at it's capabilities.
Unison comes in two flavors:
Unison can sync
For syncing desktop machine and Neo we use the latter. The recommended way to do this is the remote shell method: We start unison or unison-gtk on the desktop pc. The program will connect to the Neo via ssh an start a text-only unison on the Neo to retrieve new files or deltas and to modify files on the Neo.
For this to work, ssh may not output any text itself, because unison parses the first line of console output to determine the version of unison on the remote computer. So we setup ssh for public key authentication: