The xFS file system, part of the Berkeley NOW project, focuses on providing support to distributed applications on workstations interconnected by a very high-performance network. It provides high availability and reliability through distributed RAID semantics. Unlike Farsite, it assumes that the machines it runs on are trusted.
Frangipani is a file system built on the Petal distributed virtual disk, which is implemented in a decentralized fashion. Like xFS, it provides high availability and reliability through distributed RAID semantics, and it assumes that it runs on trusted machines. However, whereas xFS does not focus on administration issues, Petal provides support for transparently adding, deleting, or reconfiguring servers.
OceanStore, part of the Berkeley Endeavor project, is an Internet storage system that allows multiple independent storage-service providers to collaboratively provide highly reliable, location-transparent storage for Internet devices. In contrast to Farsite, the architecture of OceanStore follows a more conventional model by making a clear distinction between clients and servers.
Recently, the idea of distributed file sharing has become an extremely hot topic, led by programs such as Napster, Gnutella, and FreeNet. Links to many of these projects have been conveniently indexed by dmoz.