FreeNAS - FreeNAS is a storage operating system strong and robust enough to meet the needs of enterprise level businesses.
OpenMediaVault - OpenMediaVault is the next generation network attached storage (NAS) solution based on Debian Linux.
unRAID Server - A scalable, consumer-oriented, server operating system.
Rockstor - Rockstor is a free and open source NAS (Network Attached Storage) operating system.
Openfiler - Openfiler is the name of the open-source storage management system that is best known for its unified storage system.
StableBit DrivePool - State of the art, file based drive pooling software.