The Extent File System (efs) is Silicon Graphics' early block-device filesystem, widely used on pre-6.0 versions of IRIX. Since 6.0, xfs has been bundled with IRIX and users are being encouraged to migrate to xfs filesystems. IRIX support for efs will be read-only in versions of IRIX beyond 6.5, however efs is still very much in use on SGI software distribution CDs.
Linux, in the tradition of UNIX-like operating systems, implements file system permissions using a rather coarse scheme. While this is sufficient for a surprisingly large set of applications, it is too inflexible for many other scenarios. For that reason, all the major commercial UNIX operating systems have extended this simple scheme in one way or the other. This is an effort to implement POSIX-like Access Control Lists for Linux. Access Control Lists are built on top of Extended Attributes, which can also be used to associate other pieces of information with files such as Filesystem Capabilities, or user data like mime type and search keywords.
fistgen is the FiST language code generator, used to create stackable file systems out of templates and a high-level language. This package comes with stackable file system templates for Linux, Solaris, and FreeBSD. It also contains several sample file systems built using the FiST language: an encryption file system, a compression file system, and more - all of which are written as portable stackable file systems.
Linux NTFS provides Linux kernel drivers, a multiplatform NTFS library, and tools to create, resize, clone, rescue, query, label and fix NTFS volumes, and to undelete, resize, list, and query files for the filesystem used by Windows XP, 2003, 2000, NT4, and Vista. It also provides support for the Logical Disk Manager (LDM) that controls Windows' Dynamic Disks and is used to create software mirrors, stripes, and RAID.
RawWrite for Windows is a replacement for the DOS-based rawrite, or rawwrite program (the DOS version does not work well under Win95, and does not work at all from NT). This version is designed to work under NT/2K/XP, and 95/98/ME. It has a simple GUI, which makes it easier for first time users to create their Linux boot disks.
openMosix is a a set of extensions to the standard Linux kernel allowing you to build a cluster of out of off-the-shelf PC hardware. openMosix scales perfectly up to thousands of nodes. You do not need to modify your applications to benefit from your cluster (unlike PVM, MPI, Linda, etc.). Processes in openMosix migrate transparently between nodes and the cluster will always auto-balance.
translucency is a loadable kernel module for Linux that virtually merges two directories, making it possible to overwrite files on read-only media and compile projects (such as the Linux kernel) with different options without copying sources each time. No user-space tools have to be changed. The process is also known as inheriting (ifs), stacking, translucency (tfs), loopback (lofs), and overlay (ovlfs).