Network File System (NFS) allows the HDA to share directories and files with others over a network. You can access files on remote systems like they are local.
Subsonic is a web-based media streamer, providing ubiquitous access to your music. Use it to share your music with friends, or to listen to music while at work.
Zenphoto is a standalone gallery CMS that just makes sense and doesn't try to do everything and your dishes.
HTPC Manager combines all your favorite software into one slick interface. Do all your HTPC tasks without using 5 different interfaces!
Web based audio and video streaming application and file manager allowing you to access your music and videos from anywhere. Supports most Internet enabled devices.
Pydio is an open source software that turns instantly any server (on premise, NAS, cloud IaaS or PaaS) into a file sharing platform for your company.