I'm heading out to Australia fairly soon and for the start of my trip I'm hopefully staying with friends. However, there's a small chance that that won't be possible. I might find out when changing planes in the Far East, but there's a chance I'll step off the flight in Sydney to get a voicemail from my friends saying "Sorry, we can't pick you up after all, hopefully see you in a few days".
I know that for some cities there are websites that do very very last-minute hotel deals, to shift unsold rooms for that night.
Are there any that cover Australia (Sydney especially, if that matters)?
Otherwise, are there any good ways to find sensibly priced accommodation at the very last moment for Australia?
(My flight doesn't land until about 9pm, so I'll be too late to cancel a refundable hotel booking if I can stay with my friends as planned.)