Originally $69.99, this Waterpik Cordless Plus Water Flosser drops to $35.75 with free shipping at Walmart.com. This is the lowest price we could find by $9. It features two pressure settings, a seven-ounce water reservoir, four flosser tips, and a rechargeable battery. It gets good reviews everywhere it's sold, and it's up to 50% more effective in keeping gums healthy over string floss. Choose from five colors. Sales tax is charged in most states.