Foursquare is a location-based social networking service that allows users to share their location with friends. Some college administrators have been thinking about whether and how to take the leap into location-based services, which are also known as geosocial networking services. These platforms, which often incorporate gaming elements like badges and prizes, are downloadable applications that use the GPS capabilities of users' Internet-enabled mobile devices and smart phones to pinpoint users' locations and enable them to notify their friends of their whereabouts by "checking in." (They can also be used from a mobile website.) Friends may learn of their check-in because they're subscribed to the same location-based service, or they may see it on the feed in their Facebook or Twitter account. Location-based services have interesting implications for campus tours and orientations, events promotion, and community building, but deciding which one to use, especially in a burgeoning marketplace, can be confusing. Add to that last August's announcement of Facebook Places--the social networking juggernaut's own location-based service--and institutions may be tempted to watch from the sidelines. The user base of Foursquare and its location-based brethren like Gowalla, Loopt (which has a suite of mobile applications), and Whrrl may be little more than 10 million users combined--a drop in the bucket compared with Facebook's half-billion users--but many institutions have been experimenting with them in the few years they've been around. While users may enjoy the friendly competition that comes with the game-like aspect of these platforms, their potential as marketing tools is likely more appealing to educational institutions. Users can claim prizes, special offers, or discounts for checking in at a certain location. A restaurant or bookstore situated near a popular check-in location may offer incentives to users to drop in. Users can then comment about the deal they just received and push the message out to friends via Facebook or Twitter, thereby extending the reach of the promotion by virtual word of mouth--the essential currency of social media.