Kde 4.x dataengine for Kool Morning plasmoid
The main task is an independent API for KDE and Qt
smartCOM is a graphical serial device terminal.
JMLibs (Bibliotecas de Jandromayo)
A lightweight GUI library
Gtk 2&3 for Windows (MinGW)
Widgets library in Qt/QML
Cross Platform Light User Interface
A 3D rendering / entity engine
(Very) quickly locate files, with a nice GUI
Develop Launchy plugins in .NET languages