Jamba Juice via Great Eats offers a Jamba Juice 16-oz. Smoothie for $2 when you sign up for the Jamba Juice Insider newsletter. (The coupon will be emailed to you shortly after signing up.) That's tied with our September mention and among the best coupons we've seen for a single smoothie at Jamba Juice. Note that this offer isn't valid in Hawaii, or at Safeway, Vons, or Pavilions Jamba Juice locations.
Note that this offer may be limited to specific locations.