I recently wrote a quick PHP program to generate a heat map for geocaching.com”s ‘My Finds’. It takes their GPX file, parses it and layers the points on a UK map… it then sticks a 70’s Michael Fish on for good measure before sending it direct to your PC!

Try it here : http://www.poieditor.com/geocache-heatmap/ although you’ll need to be a signed up geocacher to use it.