What good is your GPS if the battery dies? Easy answer: useless. Luckily Casio has a solution. The G-Shock GPR B-1000 is a new GPS sport watch that has a built-in solar panel to provide backup power for your GPS tracking in the event you run through its 33-hour charge. The solar panel is on the face and will fully charge with 4 hours of direct sunlight. Back at home the watch recharges wirelessly on its power pad.