Watering tanks in pastures often become surrounded by mud, as the animals trample on the wet ground. Pennsylvania farmer Vernon Geigley solved the problem with his Water Wagon, a 125-gallon water tank mounted on a cart that's pulled by hand or vehicle. This allows him to frequently change watering sites without having to empty the tank (or wait until it's empty). Such a wagon could also be used to water livestock in areas where no water supply is available.