Lessfs is a high performance inline data deduplicating file system for Linux. Lessfs complies to the POSIX standard and is very useful for backup purposes as well as providing storage for virtual machine images. Although lessfs is a file system that is implemented in user space with FUSE, it offers decent performance. Lessfs is capable of handling data rates up to 350MB/sec. It supports filesystem encryption.
Attic is a deduplicating backup program. The main goal of attic is to provide an efficient and secure way to back up data. The data deduplication technique used makes Attic suitable for daily backups since only actual changes are stored. Main features: space efficient storage, optional data encryption, and off-site backups.