Here is a bunch of stuff I like:
(items are pretty obvious with the URL, ask me about anything specific)
Big 3 1
Water
Kitchen
Random
First Aid
Clothes
We do the same thing with flexible water bottles and hydration bladders, to keep our coolers chilled and the canteens topped off. The steel/insulated canteens (i.e. Klean Kanteen) can keep water cold for hours on their own, while the bladder can be used for refills as it begins to thaw.
You also won't have to deal with loose water in your cooler.