Good little car fridge/freezer from Brass Monkey at Jaycar. Discount applies at checkout.
These are small (15l) but work very well. They seem to be a robust and and reliable unit.
It comes with a car 12v socket or you can buy the 240v adapter should you so wish.
Specs from Jaycar:
15 litre capacity
Single zone cabinet can be run as either a fridge or freezer
High efficiency
Digital temperature controls
Dual mode operation (Economy or Maximum)
Operates on 12 or 24 volts DC
Included DC power cable to suit cigarette lighter and Merits sockets
Battery protection
Sturdy plastic case
3 Year Warranty
Showing at $249 for me. I've been looking to get one of these!