It obviously depends on where you go, but I found in my case (Japan) that having a cash card that works on OZ ATMs was by far the cheapest. Only $3 per transaction at the banks usual rate, and could draw up to $2000 each time too.
ANZ is a sham! Cant even transfer between their Australian and NZ branches without a $25 telegraphic transfer fee, let alone their branches in other countries, and to draw from atms overseas the fees are excessive too!