LibreCAD is a free Open Source CAD application for Windows, Apple and Linux. Support and documentation is free from our large, dedicated community of users, contributors and developers. You, too, can also get involved!
BRL-CAD is a powerful open source cross-platform solid modeling system that includes interactive geometry editing, high-performance ray-tracing for rendering and geometric analysis, a system performance analysis benchmark suite, geometry libraries for application developers, and more than 30 years of active development.
Scribus is a page layout (desktop publishing) program for Linux, FreeBSD, PC-BSD, NetBSD, OpenBSD, Solaris, OpenIndiana, Debian GNU/Hurd, Mac OS X, OS/2 Warp 4, eComStation, Haiku and Windows. Since its humble beginning in the spring of 2001, Scribus has evolved into one of the premier Open Source desktop applications. Encouraged by professionals and beginners alike, the Scribus Team, with support from a large and growing number of enthusiastic contributors from all over the world, is dedicated to develop and improve “one of the most powerful and useful open-source projects out there” (TechRepublic). Underneath a user-friendly interface, Scribus supports professional publishing features, such as CMYK colors, spot colors, ICC color management and versatile PDF creation. Scribus has many unexpected touches, such as powerful vector drawing tools, support for a huge number of file types via import/export filters, emulation of color blindness or the rendering of markup languages like LaTeX or Lilypond inside Scribus. The Scribus file format is XML-based and open. Unlike proprietary binary file formats, even damaged documents can be recovered with a simple text editor – sometimes a challenging …
Whether you are an illustrator, designer, web designer or just someone who needs to create some vector imagery, Inkscape is for you!
Want to find out more about how Inkscape can help you? Look at the full set of features or try it out!
Kalypso is an open source application for geospatial modelling and simulation. It is primarily developed to be a user friendly tool for GIS-based modelling and simulation of hydrological and hydraulic numerical models.
Note the main website for Kalypso is in German. However, support via the forums can be in English.