Apparently, there are some very cheap flights out of Australia to Bali with AirAsia at the moment.
And I've just seen word of a sale starting on the 15th Jan
Keep a watch out - be aware that flying with AirAsia can be cheaper than other airlines that fly direct to Bali, but they fly from Australia to Kuala Lumpur in Malaysia and from there connect to Indonesia - this means travel time can be double what a direct flight would be. For some people, saving what could add up to a few hundred dollars is worth it, and for others reducing time spent in transit is more important.
Make sure you look carefully at connections and check the total flight time as well as transit time - often the cheapest deals are the ones that leave at 6am and include a 10 hour stopover!