I used this on a kayak / snorkel trip in Belize, generally had great results, although I quite definitely miss the optical view-finder that no-one appears to placed on cameras anymore, especially underwater.
Small Fan & Mini-Air Conditioner: The Original Genuine Handy Cooler in Pink. Cools air up to 30F. Runs on USB or batteries. Genuine version with logo: Handy Cooler. (Electronics) http://www.picter.org/?p=B003KCT4UC