Oh my God i`ts movin - is the Linux only tool for creating animated PNGS. omGim alows you to easilly create and edit existing apng`s with help of GIMP or Inkscape. You can import frames from PNG, SVG, etc.
GeekCAD is a free open source CAD system. It's based on Qt4.
Features of this project:
1. dxf import, export;
2. raster bitmaps export;
3. native postscript or pdf export (in future);
4. Python scripting;
5. Parametric drawings.
A Graphical Editing Framework(GEF), for Python. It provides a canvas similar to wxArt2D and a editing framework based on MVC. The framework can be used to develop scientific and engineering tools that require graphical editing.