ClustrMaps: Embed a widget that display a map and number of visitors.

Flag Counter: Add our free counter to any webpage and collect flags from all over the world. Every time someone from a new country visits your website, a flag will be added to your counter.

Flag Counter

RevolverMaps: Every visitor leaves an eternal dot on the 3D globe, recent visitor locations are tagged by the labels showing the flag of the country as well as city and state.

Google Analytics: Get lots of statics about your website visitors and see which pages are being accessed in real-time. It doesn't display a widget, but you do need to add code to your site. Here are directions.