Sunvalley Brands via Amazon offers the TaoTronics 2-Liter Cool Mist Ultrasonic Humidifier for $19.99. Coupon code "JU5A8QTO" cuts that to $18.99. With free shipping, that's $6 under our March mention and the lowest price we've seen. (It's a current low by $4.) It features noiseless, 24-hour operation and a 360° mist nozzle. Deal ends June 20.