I spent 10 weeks in Brisbane 5 years ago. If you want to do some hiking, I recommend going to Lamington National Park. It's a subtropical rainforest about 2 hours south of Brisbane. For snorkeling, Lady Elliot Island on the Great Barrier Reef is really cool. I don't recall how far it was from Brisbane, but it's a 35 minute flight from Bundaberg.
[This message has been edited by FlyByMike (edited 08-04-2001).]