WinNc.Net is a file manager for Windows XP and 2000/ME/98/95 that replaces the use of the existing Windows Explorer. WinNc uses the same key shortcuts and the same mouse functionality as a well known filemanager for DOS called Norton Commander.
DWG to DXF Converter Pro is a batch DWG and DXF bi-directional converter that allows you to convert DWG to DXF, DXF to DWG without the need of AutoCAD. It is also an AutoCAD drawing file version converter. The Pro version supports command line.