"The Filesystem in Userspace (FUSE) project allows you install
new filesystems without touching your Linux kernel. The filesystems
run as regular programs, allowing them to use shared libraries and
perform tasks that would be difficult from inside the Linux kernel.
FUSE filesystems look just like regular filesystems to other
applications on the machine. In this article I'll look at
compFUSEd, which is a compressed FUSE filesystem. Using compFUSEd
can save a significant amount of disk space for files that are
highly compressible, such as many text documents and executable
"CompFUSEd is designed as an overlay filesystem..."