I believe that Jorn Utzon modelled the sails of the opera house on orange peels or perhaps he simply used orange peels in making a model of the Opera house - someone will know the story. It does however demonstrate a unique shape for Bobs challenge today.
I did a detour going home via Circular Quay. Really to get a shot of the opera house like this you need to be on a ferry. The ferry was packed with tourists and then I caught the regular ferry to my stop. Captain Hook (he of the hijacking saga last week) had to dodge a Wednesday evening regatta. Crikey there were a lot of yachts out although the extra doesn't really show the extent of the fleet!