Artha is a handy thesaurus based on WordNet with distinct features like global hot key look up, passive desktop notification, regular expression based search, etc. Artha may be used as a free open-source replacement/clone to the proprietary WordWeb Pro thesaurus (which is also based on WordNet) on Unix-like and Windows operating systems.
Astwar is a ncurses based simple space shooter; two little ships (asterisks), each on one side of the screen, try to shoot each other. There is network support with several multiplayer options and user extension with Scheme (via Guile) to program the little ship to do some things automatically are in the works.
GNOME Schedule is a system schedule maintenance tool. It has support for the cron and at scheduling systems. It aims to be as HIG compatible as possible. The target is to provide any sane desktop user with a tool to maintain the scheduling of his or her desktop tasks, while not requiring an understanding of the cron or at subsystems.
GNU Interactive Tools (GNUIT) is a set of interactive tools. It contains an extensible file system browser, an ASCII/hex file viewer, a process viewer/killer, and some other related utilities and shell scripts. It can be used to increase the speed and efficiency of most of the daily tasks such as copying and moving files and directories, invoking editors, compressing and uncompressing files, creating and expanding archives, compiling programs, sending mail, etc. It looks nice, has colors (if the standard ANSI color sequences are supported), and is user-friendly.
GNU Mach is the microkernel upon which a GNU Hurd system is based. It provides an Inter Process Communication (IPC) mechanism which the Hurd uses to define interfaces for implementing in a distributed multi-server fashion the services a traditional operating system kernel provides. Mach is particularly well-suited for SMP and network cluster techniques. Thread support is provided at the kernel level, and the kernel itself takes advantage of that. Network transparency at the IPC level makes resources of the system available across machine boundaries.