Use a visa card (debit, credit, prepaid) and get 8% off hotels.com
Not a great discount but better than none, minimal checking reveals probably works on all hotels.
Just a reminder that as of September last year hotels are now allowed to offer cheaper prices than online comparison websites, but are not allowed to advertise it. This means that if you call hotels with information about a cheaper price in hand they will beat/match it (hopefully beat). Usually hotels have limitations about things like it must be a third part not a 4th or 5th (e.g. the hotel must know that theyve made rooms available to these places) but some hotels are more lax than others.
tl;dr Use the link + code, take the discounted price and call the place quoting the price, theyll probably match/beat it
Update:
10% off code for some hotels au.hotels.com "AUPAY10" @ https://www.ozbargain.com.au/node/301717
Currently 16% off with cheaptickets.com although in USD.