See also:

Fresco - A windowing system derived from a powerful structured graphics toolkit originally based on InterViews. Source code, documentation, and screenshots.
GGI Project Homepage - This aims to create a portable graphics interface
MicroWindows - An Open Source project aimed at bringing the features of modern graphical windowing environments to smaller services.
Microwindows - Enabling graphical applications on embedded Linux systems - Article by Gregory Haerr at Wireless Developer Network.
PicoGUI - A client/server GUI architecture designed mainly for embedded systems, with emphasis on scalability and separation of content and presentation.
Yahoo Groups: giotto-gui - Mail list and group for Giotto embedded portable GUI, light clone of MicroWindows.

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