Here are the richest suburbs in Australia. They take into account people who work to the point where they have to pay tax, so it doesnt include the unemployed:

Top 10 National postcodes:

Postcode    State         Suburb                       Avg Taxable Income

2027           NSW      Darling Point                  $182,254

3142            VIC        Toorak                           $165,130

2110           NSW      Hunters Hill                     $164,239

6011            WA        Cottesloe                       $157,226

2030           NSW      Dover Heights                 $156,180

2063           NSW      Northbridge                     $155,112

2088           NSW      Mosman                        $154,273

3944            VIC        Portsea                          $150,771

2025            NSW     Woollahra                        $143,730

2023            NSW     Bellevue Hill                    $143,329

Queensland didn’t make the top 10 but for curiosity’s sake people residing in Ascot and Hamilton in Brisbane had an average taxable income of $113,562 (highest in Qld) whereas people residing in Hayman Island had an average taxable income of $38,557 (lowest in Qld).

And my personal Qld favourites:

Maryborough    $48,133

Hervey Bay      $48,396

Bundaberg       $49,454

Cairns             $54,222

Townsville        $64,886

Mackay           $63,843

Rockhampton  $57,366

Cooktown        $49,847

Figures are from the ATO for the 2010 tax year and only include taxable individuals