Graphite offers wire-frame drafting and 3D modeling for windows.
Edit By BS Editor: Graphite offers extremely powerful, precision wire-Frame drafting with the elegant ease-of-use that makes it productive even when only used occasionally. Running on Mac and Windows, Graphite provides an interface that lets creative people get the job done without worrying about how to run their software.

Whats New in v8?
-mid-point Line Tool
-An Updated User Interface
-Resizable Dialog Boxes
-Tear-off Tool Palettes
-Dockable Tool Palettes (coming in SP1)
-Spacebar Pan
-Universal Binary Support for the Intel Mac (coming in SP1)
-Support for File Names Over 32 Characters Long
-AutoCAD 2007 DWG/DXF Support
-Direct, Multi-sheet PDF Creation with Optional Imbedded DXF Export
-Pen Style Palette
-Eyedropper Tool
-Offset Tool in Palette
-Further User Interface Enhancements (coming in SP1) you can free download Graphite for Win 8 SP2r3 now.