SABnzbd - SABnzbd is a free/open-source cross-platform binary newsreader written in Python.
alt.binz - alt.binz is a powerful binary newsreader, for downloading and managing articles from Usenet.
NZBGet - The most efficient usenet downloader.
nzb360 - nzb360 is a featured rich NZB / torrent manager, providing dedicated support to Usenet and torrent users.
Nzbvortex - The small and efficient NZB client for OSX, optimized for performance and ease of use.
HelloNzb - HelloNzb - The Binary Usenet Tool