If you pop open your trusty cooler, that has been sitting since last season, and get knocked away by the stink, don’t replace it! Simply place a small bowl filled with barbeque charcoal inside. Seal the lid, and leave overnight. By morning, you should be able to wipe down the cooler with warm soapy water and it should be stink-free because the charcoal will have absorbed the odor-causing moisture.