There have been some very good replies here.
Passionfruit and chokoes are indeed good ones as rapid growing cover.. passionfruit and chokoes are also good food but they both hate frosts and droughts.
Hardenbergia is also very good but will not really climb .. It will need to have something to wrap itself around.
there are others as well, for example wisteria or potato vine http://www.nmessences.com/healing_images/potato_vine_b1.jpg
grapes or ornamental grapes..
I am currently covering my rainwater tanks with Wonga vine. There are other native Pandoana varieties in Australia which may be more acceptable as there are alo others from the bush banana family(was Leichardtia .. is now Marsdenia) which grow in wetter more coastal areas.