This year's Groundhog may or may not have seen its shadow, but it has got into social media. In celebration of Groundhog Day today, visitPA (The office of tourism of Punxsutawney Phil's native state, Pennsylvania) has been running a campaign via Foursquare. Those who follow visitPA on Foursquare can check in today - anywhere in the world - and shout 'Groundhog'! to unlock a special badge. Red Tettemer and Partners co-ordinated the work.