Kroger, the country's biggest supermarket chain, has joined SavingStar, a paperless grocery coupon company, increasing the number of stores using the digital service to 24,000. SavingStar, which
launched last week, offers e-coupons through its website, as well as through its phone and Droid apps. Users register their existing loyalty cards, such as their Kroger Plus card, then select coupons
online, where they can also elect to have savings deposited into their bank or PayPal account.