Display Ghostscript (DGS) is functionally upward-compatible with Adobe Display PostScript, but it has been written independently. The Display Ghostscript System provides a device-independent imaging model for displaying information on a screen. The imaging model uses the PostScript language which has powerful graphics capabilities and frees the programmer from display-specific details like screen resolution and color issues. DGS is an integral part of the GNUstep Development Environment.
GNUstep is a cross-platform, object oriented environment composed of frameworks, tools, and servers (daemons). It is very similar to the Cocoa frameworks from Apple, and tries to maintain compatibility with Cocoa wherever it is desired and possible. The frameworks provide classes for containers, distributed objects, object archiving, file management, text system, font management, image composition, WYSIWYG PostScript graphics, and more.
Gomoku.app is an extended TicTacToe game for GNUstep. You win the game if you are able to put 5 of your pieces in a row, column, or diagonal. You lose if the computer does so before you. You can play the game on boards of different size. The game has 6 different difficulty levels.
JIGS (Java Interface for GnuStep) allows Java programmers to use the GNUstep libraries from Java, but it is more than a set of bindings for GNUstep from Java: it takes advantage of the fact that Objective-C and Java are very similar languages to make it possible to use Objective-C classes from Java using exactly the same API (and vice versa). Moreover, JIGS can generate automatically wrappers for your own Objective-C GNUstep libraries.