My Foursquare makes it easy to show off your Foursquare badges and mayorships on your Wordpress blog. My Foursquare is also available as a Facebook app and an embed code so you can use it on any website.
My Foursquare shows up as a widget in your Wordpress sidebar. You can customize the widget to display your badges, mayorships, last checkin venue, and a map of your last checkin. The widget automatically uses the same font and colours of your blog.
More info here:
http://myfoursquare.net