We got one of these a couple years ago & have loved it so far.
http://www.walmart.com/ip/Cole…..ly/4810828
It can be used upright or like a conventional chest-type cooler. It has a outlet plug for the house or can be plugged into a vehicle 12v outlet. It takes around 4 hours to be ready, but once going, it will work just like a regular refrigerator. Even when not plugged in, it will function as a regular ice cooler (just keep any water away from the inside fan).