Ahhh. The sound of the great outdoors…

The throbbing, percussive, man-made rhythms of whatever gets you hard-charging up a Moab rock face or over a dusty Appalachian expanse, that is.

Nature be damned, just this one time. The Eco Extreme, from Grace Digital Audio, offers inspiration for perspiration. And it does so without the risk posed by most gadgets exposed to the elements. This mighty mini MP3 player is dirt friendly and waterproof (it floats!). And you can clap it against a slab of granite without worrying about your investment (your toe-hold is another matter). The Eco Extreme is near unbreakable, which is a good thing for the iPhone, Droid or Blackberry nestled within its rubberized outer shell.

Nature can sing again when the Eco Extreme’s 30-hour battery dies. Until then, charge on. The horizon isn’t getting any closer.