CheckoutCheckins allows you to create a heat map of your Foursquare checkins. Once you log-in to the map with your Foursquare account it uses the places you've been to generate maps, charts, graphs, and stats.
CheckoutCheckins plots your last 50 entries using Google Maps and overlays a heat map of your most recent activity. The site also produces pie charts that provide a graphic presentation of your most often visited locations.
Where Do You Go?
CheckoutCheckins is very similar to the already established site Where Do You Go?, which also allows Foursquare users to create a heat map of their travels. Once you log into the site with a Google account and then authenticate with Foursquare you can create a heat map that visualises your location data using color on Google Maps.
Denser concentrations of color on the map indicate more Foursquare check-ins at a venue at that particular location.
Create Your Own Foursquare Google Map
If you want to add a Google Map of your Forsquare checkins to your own website or blog this tutorial is very useful.
In the tutorial Michael Pucher explains how to use your Foursquare feed with Google Spreadsheets to create a Google Map that will update with your latest Foursquare checkins.