Facebook has just launched a birthday reminder service which essentially notifies you if any of your friends have a birthday in the upcoming week. This service may seem trivial, but it will probably kill all the other apps that do the same thing on Facebook. For example, Birthday Alert has over 180,000 active users. Facebook will monetize this service by allowing you to purchase e-gifts for your friends. Birthday alert services can actually be very profitable. Consider this, Bebo was initially founded to provide just this service and it has quickly grown to a large social network and now that very birthday alert service generates over $4 million in annual revenue for Bebo from e-gift purchases. According to Compete, Bebo gets about 3 million unique visitors per month. I personally find it very interesting that people would actually pay to send an electronic gift, especially those simple icons Facebook offers, and an e-card, that’s more reasonable, but I’m still surprised. Via