We just usually pack a colapsable cooler in our luggage, or buy a stryofoam one at the grocery. I actually prefer water, and soda out of a cooler. Much cooler, that the fridge. I take a few small rubbermaid containers to keep things that could be waterlogged. Cheese etc.
A fridge would be more convienient- Not running to the ice machine, but I can't bring myself to spend as much on a rental fridge, as the one I bought at home.