Just browsing the officeworks website and this is probably the cheapest item on there "Collins Debden Desk Calendar Refill 2011 Side-Hole" (http://www.officeworks.com.au/retail/products/Office-Supplieā¦) for 1 cent.
Not that its anything useful or doubt anyone would buy it for a $6 shipping(syd). But not bad for a to-do list, scrap paper or toilet paper if you intend to buy something and want to round off your total price.
says out of stock for me.
You can usually always find stuff like this in the various clearance sections.
(some people even post them as bargains, it doesnt end well)