Viking is a free/open source program to manage GPS data
Toolkit for working with and mapping geospatial data
Tool to work on map data, to check the data and generate your own maps
CAD 2D for Land Surveying and Civil
http://abc-map.fr
Multiplatform Ham Radio APRS and Mapping Program
OTB is an open-source C++ library for remote sensing images processing
Some pythons plugins to enhance fantasy maps creation with QGis
Software for distance cartogram creation
CAD 2D for Land Surveying,Civil and more