It's probably an Austrailian brown house spider.
The pics of similarly-huge spiders on house walls in the past--if you recall the picture series of the BIG spider hiding behind the clock, with just the tips of its legs sticking out--are apparently that type, and Austrailia seems to be famous for these monsters. Some of them there get BIG, and they are often found indoors.
They are often called "house spiders" there but this term isn't always clear--because there are also
black "house spiders" which are also termed "redback" spiders, or what US people call "Black Widows" of the dangerously-venemous types.
There's a lot of different species of "Huntsman" spiders however, on several continents.
Here's a page with some pics, Austrailian ones lower on down:
www.rochedalss.qld.edu.au/huntsman.htm ~