Ankle biter : small child
Bities : biting insects
Bitzer : mongrel dog (bits of this and bits of that)
Budgie smugglers : men's bathing costume, speedos
Bushman's hanky : Emitting nasal mucus by placing one index finger on the outside of the nose (thus blocking one nostril) and blowing.
Crack a fat : when a man becomes visibly excited
Figjam : "F*ck I'm good; just ask me". Nickname for people who have a high opinion of themselves.
Galah: a fellow much given to chatter
Grinning like a shot fox : very happy, smugly satisfied
Dont come the raw prawn with me: your comment is somewhat far fetched
Liquid laugh : vomit
Lunch, who opened their? : OK, who farted?
Maccas (pron. "mackers") : McDonald's (the hamburger place)
Spit the dummy : get very upset at something
Strides : trousers
Strine : Australian slang and pronunciation
Technicolor yawn : vomit
Turps, hit the : go on a drinking binge
Useful as an ashtray on a motorbike / t1ts on a bull : unhelpful or incompetent person or thing - "he, she or it is about as useful as t1ts on a bull" etc. etc.