Linger via Amazon offers the Vensmile Ultrasonic Pest Repeller for $32.90. Coupon code "9JS7I2WL" cuts it $22.37. With free shipping, that's $38 off and the lowest price we could find, although we saw it for a buck less last week. This device claims to repel mice, roaches, and other pests via a high impact pressure wave and 25KHz to 60KHz changing ultrasonic sounds. It features a 4-function switch and coverage measuring 5,000 to 6,000 feet. Deal ends January 18.