Not a cheap as low cost carriers, but some people prefer full service and direct.
Flights from Sydney (cheaper via bestjet).
Similar prices for Melbourne & Brisbane
Singapore
Economy return from $499*
Business return from $2799*
Bangkok
Economy return from $599*
Business return from $2799*
Kuala Lumpur
Economy return from $599*
Phuket
Economy return from $699*
Ho Chi Minh City
Economy return from $699*
Penang
Economy return from $699*
Phnom Penh
Economy return from $699*
Koh Samui
Economy return from $799*
Selected travel dates and days apply. Singapore - Economy 7 February - 30 March 2017, 1 May - 13 June 2017, 25 July - 13 September 2017. Business 22 November 2016 - 30 June 2017. Bangkok - Economy 15 February - 29 March 2017, 1 May - 13 June 2017, 1 August - 13 September 2017. Business 22 November 2016 - 30 June 2017. Kuala Lumpur 7 February - 30 March 2017, 1 May - 13 June 2017, 10 August - 25 August 2017 . Phuket 7 February - 30 March 2017, 1 May - 13 June 2017. Ho Chi Minh City 20 February - 30 March 17, 1 May - 13 June 2017, 7 August - 25 August 2017. Penang 7 February - 30 March 2017, 1 May - 13 June 2017, 10 August - 25 August 2017. Phnom Penh 7 February - 30 March 2017, 1 May - 13 June 2017, 25 July - 31 August 2017. Koh Samui 16 March - 29 March 2017, 1 May - 7 May 2017, 12 May - 5 June 2017. Flights between Sydney and Kuala Lumpur, Phuket, Ho Chi Minh City, Penang or Phnom Penh are via Singapore and from there are operated by Jetstar Asia. Flights between Sydney and Koh Samui are via Bangkok and from there are operated by Bangkok Airways. Other conditions apply, visit qantas.com
Hmm, seems kind of expensive given the Virgin "sale" earlier this week :)