Amazon takes $20 off the price of this Vick's Warm Mist Humidifier, dropping it to $30 with free shipping. This is the best total price we could find by $10. It has a 1 gallon capacity so it can operate up to 12 hours on one filling. It also features a medicine cup, so you can add Vick's Vaposteam or other medicated vapor to sooth and open nasal passages. With auto-shutoff there is no worry of wasting electricity or breaking the humidifier. Sales tax is only charged in KS, KY, ND, NY, and WA.