Free geocoder provided by google. may only be used in conjunction with displaying results on a Google map; geocoding results without displaying them on a map is prohibited. Limited to no more than 15,000 geocodes requests in a 24 hour period from a single IP address

Free geocoder provided by yahoo. limited to 5,000 queries per IP address per day

Geocoding web service free for non-commercial use. Lookups are throttled by your IP address to one request every 15 seconds.

Free software that adds GPS position and location data to your photos. Works on JPEG and many raw formats including NEF. The latitude and longitude recorded by your GPS unit are linked and saved to your photos. GPSPhotoLinker automatically enters the city, state and country into the metadata.

NMEA Generator generates the NMEA sentence of the GPS receiver and outputs it in a serial port.

Allows you to create an unlimited number of virtual COM port pairs and use any pair to connect one COM port based application to another. Each COM port pair provides two COM ports. The output to one port is the input from other port and vice versa.

Basic website service which takes a GPX files and geotags matching flickr photos. Allows you to specify an time offset to sync camera time and GPS time. Still standing, but appears to be broken at least as of Feb 2009

Java vector GIS viewer, reads out of PostGIS, WMS, and Others. Open Source

Swiss army knife of GPS data. GPSBabel converts waypoints, tracks, and routes between popular GPS receivers and mapping programs. Support for transformations and filtering. Key support for GPX and KML files.