FTP Synchronizer - Secure and high performance FTP File Sync product
ifttt - IFTTT puts the internet to work for you. Create simple connections between the products you use every day.
FTPSync.pl - FTPSync.pl is a PERL skript to synchronize a local directory tree and a remote FTP directory tree.
FileCloud - FileCloud is an enterprise file share, sync and mobile access solution.
FreeFileSync - FreeFileSync is a free open source data backup software that helps you synchronize files and folders on Windows, Linux and macOS.
S3 Browser - S3 Browser is the name of an easy and simple to use Amazon S3 clients for the Windows operating systems.