The Windows App SDK empowers all Windows desktop apps
Develop desktop GUI applications using PHP, HTML5, JavaScript
Node canvas is a Cairo backed Canvas implementation for NodeJS
A free C, C++ and Fortran IDE
Qt based GUI classes for the VXL Computer Vision Libraries
slab3d is a real-time virtual acoustic environment.
A fast, powerful and adaptable GUI solution
Cross-platform C framework very compact libraries and tools.
An automatic, configuration-less, GUI for Arduino projects.
A lightweight GUI library
A C++ library to easily create GUI-editable objects