Recently we came across this really clever shopping trolley designed by a fellow Aussie.
Carry Master is a three-wheeled, collapsible, highly manoeuvrable, multi-terrain trolley with the ability to carry multiple re-useable bags attached as a saddle. It has the capacity to carry up to 32kgs of goods. The combination of the three all-terrain wheels and a handlebar (which also has provision for a drink bottle) makes controlling and manoeuvring the loaded Carry Master trolley easy.
You can view more details here.