Here's the story.
IKEA opened a new store in Malmo, Sweden and didn't have a lot of money to advertise about it or let people know about it. So they hired a small advertising agency called Forsman and Bodenfors to create a special launch campaign.
Now, what the agency did was that it created a Facebook profile for the store manager, Gordon Gustavsson. and over a period of 2 weeks, it uploaded images from IKEA showrooms to his Facebook photo album. Then they announced that the first person to tag their name to a product in the pictures, won it.
Before you knew it, word got out and thousands of Swedes were begging for more pictures so they could tag themselves a new sofa, a new bed etc. At this point, thousands of Swedes, were spreading pictures of IKEA showrooms all around their profile pages!