• Kongregate is a Flash game portal with an achievement API developers can tap into. Users sign up, play games, win achievements within different Flash games and earn badges. Each badge is worth so many points and the more points you earn the higher level your account becomes. Kongregate even links certain achievements to GameStop rewards for real-life bonuses.
• GetGlue is a social "check-in" service based around what you are watching or reading. GetGlue is essentially a great marketing plug for television networks, movie company's, and book publishers. GetGlue calls it's achievements "stickers", which you earn by checking into a show, movie, or book so many times or on a certain day. For example, if you check into a television show on the airing of a new show, chances are you'll earn a sticker to show off you "were there."
• Foursquare is another social "check-in" based based around where you are; are you at Starbucks? Or are you at Chili's? You earn points by checking in which helps you beat friends in a weekly "battle" to see who received the most points.  Achievement's on Foursquare range from when you check-in to a certain place (like a bar at 2am) or with a lot of people (swarm badge I believe is 150 people) or by adding a "shout" to your check-in (adding "it's a boy" in a hospital is one achievement.)
• Klout is a service that puts a number to your social influence. In this example, Klout isn't an engaging social service per se, but provides achievements to user activity. If you visit the site for a few days in a row, you're awarded. If you try out all the different features, you're rewarded. As your score goes up, you earn achievements.

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