If you're just after domestic prices, return flights from $68 between Melbourne and Sydney is a great start on Jetstar's weekend sale (which includes some international routes too), but this post is more for the international routes.
AirAsia, Jetstar, Scoot - all have sales on at present all over SE Asia and nearby, so I just combined them all into one post of the cheapest I could find on every route. There may be cheaper on some routes still if you hunt around. Always check both one way and return for prices.
Full post with all the routes with examples here
Summary: (as it's too big to fit the whole post in ozb's 50,000 character limit):
Sydney to Singapore (30 Jan - 20 Nov) from $380
Melbourne to Singapore (30 Jan - 20 Nov) from $364
Perth to Singapore (30 Jan - 20 Nov) from $317
Sydney to Kuala Lumpur (30 Jan - 20 Nov) from $386
Melbourne to Kuala Lumpur (30 Jan - 20 Nov) from $355
Perth to Kuala Lumpur (30 Jan - 20 Nov) from $228
Sydney to Tokyo (30 Jan - 20 Nov) from $582
Melbourne to Tokyo (30 Jan - 20 Nov) from $551
Perth to Tokyo (30 Jan - 20 Nov) from $621
Sydney to Bangkok (30 Jan - 20 Nov) from $394
Melbourne to Bangkok (30 Jan - 20 Nov) from $367
Perth to Bangkok (30 Jan - 20 Nov) from $290
Sydney to Seoul (30 Jan - 20 Nov) from $570
Melbourne to Seoul (30 Jan - 20 Nov) from $577
Perth to Seoul (30 Jan - 20 Nov) from $559
Sydney to Athens (30 Jan - 20 Nov) from $867
Melbourne to Athens (30 Jan - 20 Nov) from $853
Perth to Athens (30 Jan - 20 Nov) from $760
Sydney to Ho Chi Minh City (30 Jan - 20 Nov) from $311
Melbourne to Ho Chi Minh City (30 Jan - 20 Nov) from $375
Perth to Ho Chi Minh City (30 Jan - 20 Nov) from $311
Sydney to Chennai (30 Jan - 20 Nov) from $588
Melbourne to Chennai (30 Jan - 20 Nov) from $570
Perth to Chennai (30 Jan - 20 Nov) from $505
Sydney to Kota Kinabalu (30 Jan - 20 Nov) from $419
Melbourne to Kota Kinabalu (30 Jan - 20 Nov) from $335
Perth to Kota Kinabalu (30 Jan - 20 Nov) from $291
Sydney to Langkawi (30 Jan - 20 Nov) from $469
Melbourne to Langkawi (30 Jan - 20 Nov) from $364
Perth to Langkawi (30 Jan - 20 Nov) from $311
Sydney to Jakarta (30 Jan - 20 Nov) from $483
Melbourne to Jakarta (30 Jan - 20 Nov) from $376
Perth to Jakarta (30 Jan - 20 Nov) from $221
Full post with all the routes with examples here
You can follow us at Beat That Flight for more deals, error fares, promos and sales, on Youtube, on Facebook, or on Google News.
Any Queensland options?