I must admit, I'm not as familiar with the Australian movie scene as much as I am with the US/Canada and UK movies.
There are some notable exceptions, of course, like Mad Max and Breaker Morant (haven't seen it for a few years though), and recently I've finally watched Romper Stomper. Over the years I've caught some others like Man from Snowy River, Picnic at Hanging Rock, and then the 'pop culture' movies like Crocodile Dundee and Muriel's Wedding.
I'm sure there are others I've seen that I'm just not remembering off the top of my head.
If anybody has some suggestions on 'Must See' movies, feel free to give your list.