NZBGet.com - Fast, reliable, and feature-packed NZB downloader.
FreeFileSync - FreeFileSync is a free open source data backup software that helps you synchronize files and folders on Windows, Linux and macOS.
NZBGet - The most efficient usenet downloader.
rsync - rsync is a file transfer program for Unix systems. rsync uses the "rsync algorithm" which provides a very fast method for bringing remote files into sync.
SABnzbd - SABnzbd is a free/open-source cross-platform binary newsreader written in Python.
GoodSync - GoodSync provides highly reliable file backup and synchronization for both individuals and businesses.