Open source file storage and sharing apps
|Syncthing - http://syncthing.net/|
Continuous Replication / Cluster Synchronization. MIT licence, source on Github
|ownCloud - http://owncloud.org/|
AGPL file storage, contacts, calendars, bokmarks and basic editing
|Seafile - http://seafile.com/en/home/|
File synching and sharing. Licence GPLv3, source https://github.com/haiwen/seafile
|SparkleShare - http://sparkleshare.org/|
Self hosted, collaboration and sharing tool. It allows you to instantly sync with Git repositories and is available for Linux distributions, Mac and Windows. LGPL, source on Github
|Syncany - https://www.syncany.org/|
open-source cloud storage and filesharing application. It allows users to backup and share certain folders of their workstations using any kind of storage. GPL 2.0, source on Github.
|Tahoe-LAFS - https://tahoe-lafs.org/trac/tahoe-lafs|
Distributes user's data across multiple servers. Restful API. GPLv2 with many linking exceptions.