One good implementation that has not been mentioned is http://www.kongregate.com http://www.kongregate.com. More good examples are http://www.Yelp.com http://ww

One good implementation that has not been mentioned is http://www.kongregate.com http://www.kongregate.com. More good examples are http://www.Yelp.com http://www.Yelp.com and http://www.Mahalo.com http://www.Mahalo.com. I almost feel like http://www.thewhuffiebank.com http://www.thewhuffiebank.com is also a good example of an attempt at microreward and reputation system on a grander scale.