The wireless speaker for adventure seekers, Ultimate Ear’s UE Roll is about the size of a round flask and pumps out some serious 360 degree sound. A plasma-coated acoustic skin renders the Roll waterproof to IPX7 standards (1 meter below the surface for 30 minutes) as well as dirt, dust, and stain resistant; hell, if it gets dirty, just wash it in the sink. It’s also [obviously] Bluetooth enabled, lasts 9 hours per charge of its lithium-ion battery, and boasts a built in marine-grade bungee cord for attaching it to your gear. And if one of your friends has another — or any UE speaker, for that matter — use the UE Roll app to Double Up and seamless synchronize music playback across both devices for surround sound.
Grab one at Amazon – $100