Viking is a free/open source program to manage GPS data
Toolkit for working with and mapping geospatial data
GPS track editor for editing tracks and planning (multiple) day tours
Plugins for OpenCPN
FastVersion is a Qgis plugin for data versioning in a Postgis database
Java Swing component for integrating OSM maps into your Java app.
Open Street Map (OSM) tools, OSM/XML parser, tag extractor