For anyone using a cooler on the bike...or trailer, I found something interesting...
Its a heavy duty cooler with twice the insulation that a normal discount-store cooler has. Of course it aint cheap...but I ordered one anyway....I plan to use it primarily in my work truck, but also, I might build a rack for it on my bike or trailer. They claim its a lot better at keeping things cold. I'll post a report after it comes in and I've had a chance to use it awhile.
They have 25 QT versions with and without handles. I ordered the 25 QT Roadie.
http://www.yeticoolers.com/roadie-c-17.html
http://www.yeticoolers.com/assets/images/img-roadieseries.jpg