Uber have partnered up with Virgin Australia to offer users $40 Uber credit when they book a flight with Virgin Australia.
Need to book a flight by 14 November for departure between 1 January 2015 and 7 October 2015. The Uber promo code will be emailed to you by 21 November by Virgin. Says that the Uber code is unique so can only be used once.
The credit is only available to first time Uber users. Probably no first time users left on OzBargain but may get you a free ride to the airport if you give the code to your travelling companion.
EDIT: Looks like Virgin cut this promotion short due to a customer backlash against partnering with an organisation like Uber that's deliberately trying to avoid taxi regulations.
I think it's nearly time for Uber to pivot their marketing approach.