DWG DXF Converter lets you batch convert DWG Files into DXF files.
It is a powerful program that allows you to convert DGN files to DWG.
API for NET developers that supports AutoCAD DWG, DXF, PLT and other CAD formats
Solution to view, print, review, edit, modify, protect, convert DWG DXF DWF drawings.
It is an open source ground control station which accepts NMEA, SiRF and others.