Open Source Solid Modeling CAD
BRL-CAD is a powerful cross-platform constructive solid geometry solid modeling system that includes an interactive geometry editor, ray-tracing for rendering & geometric analyses, network distributed framebuffer support, image & signal-processing tools.
Global visual guides for Windows
The Guides application is designed to provide global access to some helpful visual guides. The project is very early in development. Please feel free to jump in and make changes!