OK, starting from http://dataturbine.org/content/usage-dataturbine-kml-plugin

Modified my serial accelerometer driver to add fixed lat, long, elevation - http://code.google.com/p/oss-dataturbine/

under dev/adxl-kml

Run RBNB, source, add TrackPlugIn like so

http://code.google.com/p/oss-dataturbine/
java -cp $RBNB_HOME/bin/rbnb.jar:/usr/local/rbnb/apache-tomcat-5.5.12/webapps/webTurbine/WEB-INF/classes TrackDataPlugIn

Then the KML plugin:

http://code.google.com/p/oss-dataturbine/
java -cp $RBNB_HOME/bin/rbnb.jar:/usr/local/rbnb/apache-tomcat-5.5.12/webapps/webTurbine/WEB-INF/classes TrackDataPlugIn
java -cp $RBNB_HOME/bin/rbnb.jar:/usr/local/rbnb/apache-tomcat-5.5.12/webapps/webTurbine/WEB-INF/classes TrackKMLPlugIn

Then try URL for earth of http://localhost:8080/RBNB/TrackKML/TrackData/adxl-kml?d=500

Hmm, no tracks found.