The GPX viewer is a 100% client-side JavaScript GPX file viewer that uses Google Maps to map waypoints and tracklogs.
GPX files are a standard GPS data format that is supported by many software applications. It is an XML based data format which lends itself nicely to being parsed in JavaScript.
Since it is written entirely in JavaScript, this script can be added to any web page with minimal effort and little or no server code. Just copy a GPX file to your web site, make a web page with an embedded Google Map, include the script, and initialize it.
This script is meant to be customized to some extent. The default formatting for Waypoints is to show the available GPS data, but since it is Javascript, you can easily customize it to suite your needs.
More information can be found here http://notions.okuda.ca/geotagging/projects-im-working-on/gpx-viewer/