Here's an object category I had no idea existed: Floating coolers. These are apparently popular among people with swimming pools, people who vacation on lakes, and kayak campers. (The latter category travel to their campsite by kayak, carrying their camping gear on-board.) Being a relatively new product category that targets different use cases, there is no established form factor. What I found most interesting are the user reviews: The people who love these things, really love them.

This $66 Rangland River Cooler is inflatable. This targets the kayak crowd. It's meant to be loaded up with food and drink, then towed, reducing weight on the kayak. It's made of PVC, and the manufacturer says the underside is triple-layered to offer "extreme protection against scratch and puncture."

This $40 Pittman Floating Ice Chest is also inflatable, and they offer both a hard-sided cooler and inflatable cooler option. However, these apparently lack the durability (according to reviewers) of the Rangland model. It's perhaps better suited to pool parties than towing down a river; whereas Rangland mentions beefing up the underside of their offering to protect against rocks, this Pittman model comes with a patch kit, which doesn't sound reassuring.

This rigid $130 CreekKooler model is presented as being primarily for pool parties. But it gets rave reviewers from kayakers and boat people. An interesting use case I hadn't thought of; one reviewer says he bought a second one, to use as a floating trash can.

This $60 Big Bobber Floating Cooler seems like a poor design: As you can see in the product photos, the spherical shape means it can easily tilt and take on water. On top of that, the lip where the two halves meet seems cheap and poorly executed. User reviews back both of those points up.

Lastly, this $300 Amphibious Cuddy Crawler has wheels, making it easy to transport on land. Reviewers raved about this feature—coolers loaded up with ice and drinks can get heavy—though some complained about the wheels falling off. There is a rather glaring design flaw: The wheels are meant to be removed for towing-in-water applications, and they are attached to the cooler by Velcro. As one reviewer pointed out, trying to pull the cooler across a gravel parking lot easily jostles the wheels off. Caveat emptor.