OKTravel is an Australian travel site using Google Maps to present information about Australian towns and cities.
The featured Google Map on the site has some very interesting design features. The map has custom markers and a custom marker clustering solution. The markers themselves have a nice mouse-over effect that dims out the other markers on the map. Also, when you click on a map marker, an information window opens and the rest of the map is dimmed.
If you click on the '+' symbol at the top right of the map a tool bar opens. The tools include a line measuring tool, a polygon measuring tool to measure areas and an overlay that shows the Australian states.
Oh, and the map also has some interesting information about Australian towns and cities with links to each town's individual page on OKTravel