As soon as I enter the sanctuary of my favorite spa I am overwhelmed by the delicious smell. I have often scouted the room to find evidence of a candle or table top diffuser. I have wondered if is it just the mix of all the products in use. Silly me. Stealthily parked in the corner of each room is an ultrasonic essential oil diffuser. These tidy sized units operate with a scant amount of water and a few drops of essential oils. Now I can enjoy this olfactory pleasure at home.