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.
losetup-utils are three bash scripts that attempt to make the use of losetup a bit easier and faster. losetup can be fast, easy, and practical if you need to transport sensitive information over the Internet or in CD's, DVD's, or a pendrive. Also, if you want to store private data on your hard disk or in the cloud, an encrypted volume can be a convenient choice. The types of encryption can be any installed on the system.