Nixon's Lodown digital watch is pre-programmed with tide charts for 200 beaches around the world for the next 15 years. It uses a backlit LCD screen which shows a pixel graph of the current surf height. It's made from reinforced polycarbonate, is water resistant up to 100 meters, and costs about $90. Although I don't understand how they managed to pre-program tides for the next 15 years. Isn't it just a bunch of wild guessing at that point?