As soon as you arrive in Australia, you're going to hear about Fraser Island and The Whitsundays. Everybody sees Fraser Island by 4X4, which is amazing and has to be done, but while there I highly recomend you also splurge and pay the $75 to take the breif scenic flight over the island. How many places in the world do you get to use the beach as your runway? You get to see things from a completely different perspective; you also get to see things you probably won't make it to by car like Butterfly Lake. Chances are on a nice day you'll spot Stingrays, Manta Rays, Dolphins, and maybe even sharks. This is one of those things you need to put in perspective, I know $75 sounds like a lot, but take a night off the drink and do this instead.