Well... the bird eating or whistling spider is found in the Northern Territory and Western australia.. it gets the size of a dinner plate
Not so dangerous though, the Sydney Funnel Web spider is much worse and they sometimes come into houses (I woke up with one inches from my nose at age 3 or 4.. it took me a while to be ok with spiders after that). Shark attacks get a lot of publicity but they are really not that frequent. Lots of things are more likely to kill. Even at the beach.. stone fish, blue ringed octopus, box jellyfish, crocodiles... Snakes are a real issue though with several deaths this year from Brown snakes including one young girl in a town nearby to here. The taipan is pretty bad with it's love of laundries, red belly black snakes can be nasty if they feel threatened. The King Brown is the real bad one though and it's darn common. We even have giant ants.. not quite as big as in the film THEM! but an inch is pretty big for an ant. Google bulldog ant, they are cute! I was attacked by crazy ants north of the whitsundays once, that really hurt
In backyards (in the central west and later northern NSW) I've had blue tongued lizads a plenty, shinglebacks, some sort of foot long skink (that my cat brought into the house which is part of why she's an indoor cat now) a nest of brown snakes, a wedge-tailed eagle, black cockatoo's, hibernating frogs.. I've had roos run down my street, possums fighting on my roof, I've nursed a juvenile bat back to health when its mother died around the corner and more little critters than I can easilly remember, that's all in town!