In a campaign designed by the seoul branch of advertising agency Cheil, Tesco Homeplus supermarket opened last fall
a virtual grocery store in a south korea subway station, permitting users to shop using their smartphones.

A large, wall-length billboard was installed in the station, designed to look like a series of supermarket shelves
and displaying images and prices of a range of common products. each sign also includes a QR code.
users scan the code of any product they would like to purchase, thereby adding it to their online shopping cart.
after the web transaction is completed, the products are delivered to the user's home within the day.

The strategy makes productive use of commuters' waiting time,
while silmultaneously saving shoppers time spent going to the supermarket

See the movie and more info from this link:
http://www.designboom.com/weblog/cat/16/view/15557/tesco-virtual-supermarket-in-a-subway-station.html