I came across this via a colleague. Check out this simple little idea to promote the new IKEA store in Malmo, Sweden. You probably can’t do it now due to the Terms & Conditions changes (see Westfields campaign) as it gets into people’s news feeds and status. Although I would think it was ok and also had a huge viral element to it as well.
They were able to create an interactive campaign and a live photo album. Watch it!