DWG FastView - DWG FastView for Windows is a lightweight dwg/dxf drawing viewer and editor produced by Gstarsoft, no need of dwg format conversion, vector graph magnified without distortion and full compatible with AutoCAD DWG/DXF.
Autodesk DWG TrueView - Get a free DWG viewer to view, open, edit, and convert .dwg files, the native file format for AutoCAD files. DWG Trueview includes DWG TrueConvert.
de·caff Viewer - The de·caff Viewer version 3.
Autodesk Design Review - Design Review lets you view, mark up, print, and track changes to 2D and 3D files.
Free DWG Viewer - Free Viewer for DWG, DXF, DWF View AutoCAD DWG/DWF/DXF files View & measure DWG, DXF, DWF
ZWCAD Viewer - Cross-Platform .DWG | .DXF | .DWT R12-2013 Viewer