gvSIG is an easy to use Java desktop GIS. It has a friendly interface, and can access some popular formats (e.g. SHP, DGN, DXF, DWG, TIFF, JPEG, ECW, SID, etc). It will integrate in a single view both local vector and raster data, as well as remote data through WMS or WCS. It allows layout design for printing. It is meant for end-users of geographical information, and currently has Spanish, Valencian, English, and 6 more interfaces. It's designed to be easily extended.
OLIVER is MassGIS's OnLIne data ViewER. Written as a stand-alone Java application (and deployed via Java Web Start) it allows you to browse, view, and download (if supported) data from the MassGIS maintained WMS and WFS servers. In short, it is a specific take on a WMS/WFS client.
MapMemo allows you to drag your files onto any graphic (map, photo, scan, illustration, screenshot, etc.), and thus give them a visual, location-based relation. It uses only aliases of your files which, when you click on an appropriate location, will open in their original application. You can use layers, info windows, colors, and comment fields to organize your files on the map.
nmeap is an extensible parser for NMEA-0183 (GPS) data, written in portable C. It has a small footprint, is portable, extensible, and I/O agnostic. It is suitable for Linux, Win32, and embedded systems. It has built in support for most useful standard NMEA sentences, and is extensible to add additional standard and proprietary sentences. It builds to a linkable library for embedding in other applications.
gipfel is a tool to find the names of mountains or points of interest on a picture. It uses a database containing names and GPS data. With the given viewpoint (the point from which the picture was taken) and two known mountains on the picture, it can compute all parameters needed to compute the positions of other mountains on the picture. gipfel can also generate (stitch) panorama images.