Traveling this week, I checked into Boston's Logan Airport on Foursquare. I noticed that a special 'local offer' existed. Hoping it was discounted Dunkin Donuts coffee, I took a look and uncovered one of that strangest Foursquare Mayor Offers I have seen: The mayor of Logan Airport gets Massport 'Swag'... which no doubt means that someone working inside of Logan is wearing an "I Love Boston" sweatshirt.

More seriously: this is a lesson in crafting compelling offers... which in turn drive activity, engagement, sharing, etc. Discounts (see Gap, McDonalds) and giveaways are more attractive, appeal to larger audiences, and likely drive new users / fans / check-ins.