Avatar: The Last Airbender (the complete series) in full HD is currently on sale for $24.99 on the Australian iTunes store. Normally sells for $49.99-59.99, so this is a pretty good deal.
The show itself has a 100% average tomatometer score on Rotten Tomatoes, so it’s well worth a watch.
Don’t forget cashback when purchasing from iTunes!
As always, bear in mind that you either need iTunes or an Apple device to play this, as iTunes-bought movies and TV shows are encrypted with DRM.