Desktop GIS
QGIS
QGIS (previously known as Quantum GIS) is a cross-platform free and open-source desktop geographic information system (GIS) application that provides data viewing, editing, and analysis.
uDig
uDig is an editor of GIS data and a Java platform for the development of new GIS applications. It was developed taking into account OpenGIS standards for the web, especially Web Mapping Service and Web Feature Service standards.