darktable is an open source photography workflow application
Free and open source voxel art tools - editor, thumbnailer and format
Display, convert, and edit raster image and vector image files
3D Procedural Modelling and Procedural Texturing Tool in OpenGL/C++
Deep paint and stop-motion animation software
Library to correct optical lens defects and lens database
A 3d rendering framework
Free drawing software for Windows, Mac OS X, and Linux
Not your usual Architectural Modeler