Sztrokia via Amazon offers its Sztrokia Aromatherapy Essential Oil Diffuser for $39.99. Coupon code "M2EKJGZX" cuts that to $27.99. With free shipping, that's at least $20 less than what eBay vendors are charging. It features 14 colors, two mist modes, and auto shut-off.
Anypro Global via Amazon offers the Anypro Ultrasonic Cool Mist Room Humidifier for $36.99. Coupon code "CODE2L2L" drops it to $25.89. With free shipping, that's $24 off and the lowest price we could find. It features a timer, adjustable output, and night light.