Cheil Worldwide in South Korea took home the coveted prize for creating a virtual grocery store in a Seoul subway for Tesco (the British chain that's been renamed Homeplus in Korea). The shelves are laid out just like a physical store, and the items are fully shoppable via smartphones and QR codes. People waiting for their trains can scan items right into an online cart, with the items to be delivered to their homes. A case-study video is here.

What it is: The "Homeplus Subway Virtual Store" was an idea conceived by Cheil to help the retailer get an edge over its larger rival, E-mart. Instead of trying to persuade consumers to visit the store, Cheil had the idea to bring the store to busy, hardworking people. It recreated lifelike images of store aisles in subway stations that were interactive and allowed people to shop from the store simply by taking pictures of the products with their mobile phones. Their orders were later delivered to their homes. Although engagement with the idea was only in the tens of thousands, online sales for Homeplus jumped by 130%, the client said.
Link:
http://news.softpedia.com/news/Samsung-and-Cheil-Use-Transparent-LCDs-on-South-Korean-Subway-Stations-229513.shtml
http://www.adweek.com/cannes-lions-2011/media-grand-prix-goes-south-koreas-cheil-virtual-grocery-store-132766
http://adage.com/article/special-report-cannes/south-korea-s-cheil-captures-media-grand-prix-cannes/228319/
http://youtu.be/OIvz9TXTlS0