Tonerone Direct via Amazon offers the Tonerone 13.5-oz. Ultrasonic Aromatherapy Essential Oil Diffuser and Cool Mist Humidifier in Yellow for $24.99. Coupon code "L29T9C5W" cuts the price to $12.49. With free shipping for Prime members, that's $2 under our January mention, $13 off list, and the lowest price we could find. It features a 13.5-oz. capacity, two mist modes, seven LED light colors (with steady and rotating modes), four timer settings, and auto shutoff. Deal ends May 20.