GetFlight is a Google Maps based application that displays the cheapest flights in and out of Australia. The application tracks sale fares for the four major domestic carriers and some of the largest international airlines that operate in and out of the country and displays them on a map.
To start you can just click on one of the major cities and the cheapest domestic and international flights are immediately shown on the map. It is also possible to type in your starting point and your destination of choice to see the best deals for that journey.
If you select the 'search direct' button you can also define the dates you wish to travel and select which airlines you wish to fly with.