We have gone over portable USB power before, but this one is the coolest by far.   It is a waterproof 350 Lumen light stick that can last up to 72 hours. It has 3 power settings plus a flash mode. It can also charge your phone or tablet device thanks to a 5200mAh battery with a 2.0 amp USB output.  The stick is waterproof which makes it perfect for just about any outdoor application.  Check it out via Amazon.