NEW18AUS
Cheapest price. It can even get cheaper with voucher EMCPURT53 but it just works for USA users.
$20 aud voucher with new accounts.
Decent projector. 2 years old but with good features (lens shift, Rec. 709, short throw ratio, 3D). It specs almost match with much more expensive Benq 2050 that costs $750 - $ 799 USD but is better though.
3 years warranty.
Review: http://www.projectorcentral.com/viewsonic-pro7827hd-projecto…
Downside is input lag is 50ms. Enough for most people though.
price coming up as 730$AUD before the $20AUD discount.