Today only, Groupon discounts a selection of apparel, electronics, home goods, pet items, and more to $20 or less during its Plenty for Twenty or Less Sale. Shipping adds $3.99, or bag free shipping with orders of $34.99 or more. A couple of best bets, both with $3.99 for shipping:

• RevJams Satellite Bluetooth LED Speaker for $10 (low by $6)
• HealthSmart Mist XP Ultrasonic Cool Mist Humidifier for $20 (pictured; same at Amazon via Subscribe & Save, low by a buck)