Off the coast of Brisbane, there are three sand dune islands. It's crazy to think that without the tree roots to hold it together, then the entire island would be swept into the ocean...
The less touristy version, Moreton Island, is the third largest and more hippie like-- sign me up. Without paved roads the only way to get around is a 4WD. You can either hire one or go on a tour with a group.
And because the barge going over to the island (an hour and half) is down to one boat versus two, the cost is crazy steep: $300 for two days, transport included, and camping (with really stinky sleeping bags, I might add, and hamburgers for supper!)