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.
Addresses is a GNUstep address book that consists of a full-featured address book manager application, a source-code compatible replacement for Apple's AddressBook.framework (for accessing and manipulating address data programmatically), a framework of view/editor classes that make it easy to use Addresses from your own programs, and a number of tools. It is easy to use by both users and programmers and can store almost all imaginable data, including multiple phone numbers, emails, and addresses, photos, AIM/Jabber/ICQ/Yahoo IM details, and notes. It supports drag-and-drop and integrates well with GNUMail.
SMS Framework is an Objective C framework for decoding SMS messages in PDU format to objects. It is easily usable in Cocoa and GNUstep environments, and it reduces developer responsibility for decoding messages to extracting the raw messages from the phone. The XCode project file contains three targets: one system wide framework, one framework to include in applications, and a small application for testing the framework.
Green Dome GNUstepWeb for Mac OS X provides a WebObjects 4.5-like environment for Mac OS X (with some support for WO5 additions). It is composed of modified versions of the standard GNUstepBaseAdditions, GDL2, and GNUstepWeb frameworks, built to run on top of Apple's Cocoa frameworks. The GNUstep frameworks have been built with Xcode as true Mac OS X frameworks. Thus, they may be used as any other framework under Mac OS X. Note that this is a standalone package that does not require or interoperate with a separate GNUstep installation/environment. It is not intended to provide a complete GNUstep environment, such as would be expected of a full GNUstep installation.