Supermarkets Grocery-Cart Wars

In the battle for customers, high tech is one way to compete with -- and sometimes beat -- low prices

As Helaine Alpert steers her shopping cart down one aisle and up another at the Food Emporium in Scarsdale, N.Y., an overhead electronic billboard flashes the specials of the day. On the rim of Alpert's cart, a 6-in. by 9-in. video screen automatically displays a list of specials in each aisle she passes. Electronic alert: Cup O' Noodles on sale, two for $1; veal chops, $6.99, a dollar off the regular price. "I used to scour all the flyers for bargains," says Alpert, a lawyer from nearby Edgemont, but now the computer takes care of that. Her basket filled, she takes...