PimpRig posted a review up on an aluminum laptop cooler from Titan.

As far as the amount of power it uses to run. I plugged it into the laptop that had a fully charged battery. With the laptop and Coolerpad running under full load it took 1 hour and 52 minutes for the battery to run out completely. When I ran the laptop without the cooler it ran for 2 hours and 23 minutes. Your results will vary depending on your laptop's power usage but this should give you an idea of how much juice this cooler will use if you run it via USB power.

Titan Serina Stylish Laptop Cooling Pad