Waterproof and wireless, this puts the loud in loudspeaker. Bumping 36 watts of compact, bass-heavy power through four separate drivers, you can attach it almost anything with the bungee strap and carabiner — and it's shockproof, so it can take a beating. Wirelessly pair two of these for up to 12 hours of crisp stereo sound. And bonus: this speaker will serve as an emergency power bank for any USB-equipped electronics in a pinch. Talk about double duty.