In Reply to: arriving 28th march posted by locky on Saturday, 28. February 2009 at 18:17 Bali Time:
You won't get 'ripped off' by paying in Aussie dollars. You might end up about a couple of dollars different to what the official exchange rate is, but you'll spend more than that in fees and petrol trying to change to US$ in Australia before you go. Any place that advertises 'no fees' in Australia just has them built into a lower exchange rate - and often has a minimum buy (like Aus Post $200 minimum).
It takes no extra time to pay in Aussie dollars when you get there - and like you said yourself, you'll get some rupiah change to pay for the taxi.
I've always looked online the night before I go and have a rough idea of what it should cost me in Aussie dollars and it's always been within a dollar or so of what I expected - and the change in rupiah is so close it's less than a dollar difference too.
Also, for the last part of your question - there are ATMs at the airport if you need them. I've used them in the past with no trouble.