Resilio Sync

Resilio Sync (formerly BitTorrent Sync) by Resilio, Inc. is a proprietary peer-to-peer file synchronization tool available for Windows, Mac, Linux, Android, iOS, Windows Phone, Amazon Kindle Fire and BSD. It can sync files between devices on a local network, or between remote devices over the Internet via a modified version of the BitTorrent protocol.
Although not touted by the developers as an intended direct replacement nor competitor to cloud-based file synchronization services, it has attained much of its publicity in this potential role.