Here's a couple more options:
As already mentioned; get a thermoelectric cooler. These tend to generate temperatures about 30 deg. under ambient (or 40 deg. over ambient in the heating mode).
Get a DC to AC power converter and use it to power a small 120-volt AC refrigeratir or chest freezer.
Dr. Mark (STL)
Ph.D. (honorary) Bovine $hitology
A thin line separates paranoia from an acute understanding of reality.