EncFS is an encrypted pass-through filesystem which runs in userspace on Linux (using the FUSE kernel module). Similar in design to CFS and other pass-through filesystems, all data is encrypted and stored in the underlying filesystem. Unlike loopback filesystems, there is no predetermined or pre-allocated filesystem size.
FSter is a virtual filesystem implementation based on FUSE and exploiting Tracker's indexer to allow access to files according to the metadata with which they’re associated. Its behavior is highly customizable with XML configuration to describe in detail the desired hierarchy of files.
CarvFS is a user space FUSE filesystem aimed at computer forensic tools that process disk and/or memory dump images or other large data files. The filesystem allows CarvPath-aware tools to use CarvPath annotations as a way to designate partitions, files, alternate streams, processes etc. within a disk or memory image as a string, making them available trough the filesystem as a pseudo file that can be handed to other tools. This removes the need to copy the information out of the disk image and reduces storage requirements.