GTK+: GIMP Toolkit
Library to build graphical user interfaces (GUIs) originally for X Window. Designed to be small, efficient, flexible. Coded in C, in very object-oriented style. Language bindings: …
GtkExtra--
Provides C++ wrappers for GtkExtra, for use with Gtk--. This includes the GtkPlot and GtkSheet widgets, among others.
Loki Setup Graphic Installer
Automated GUI installer and setup utility for the X Window System.
TiLP - Ti Linking Program
Formerly GtkTiLink, provides GtkDll and GtkHeader-Installation packages for Windows.
VDKbuilder
Rapid application development tool based on VDK (The Visual Development Kit), a C++ wrapper of the outstanding Gtk+ widget set library. [Open source, GPL]
ZMW - A Zero Memory Widget Library
A C library allowing to create GTK based GUI with not a single bit of memory per widget.