Sporttracks is a free GPS software based on donations from happy users. Sportsim like Sporttracks because of an esay user interface and a strong statistical package. Its easy to transfer track data between Sportsim and Sportracks with .gpx files. Sporttracks does use the .NET framework so it's a quick download and installation process.
Check it out, and let us know if you see a value added by using Sporttracks for your needs.
We are considering to recommend Sporttracks together with Sportsim on our main site.