ownCloud is a free and opensource file sync and share app which is self hosted.

GNU MediaGoblin (MediaGoblin or GMG) is a free, decentralized Web platform (server software) for hosting and sharing many forms of digital media.

Shotwell is an image organizer designed to provide personal photo management for the GNOME desktop environment.

Piwigo is photo gallery software for the web, built by an active community of users and developers.