I recently discovered an interesting and informative website called the 'Psychology of Games' created by Jamie Madigan. The website provides discussions on how the psychology behind games shapes our behavior, manipulates our beliefs, and rigs our purchasing decisions. There are loads of articles to read through and they are well written. Some of my favourites include Why We Get Nostalgic for Old Games, Anonymity and Anti-Social Behaviour and The Psychology of Immersion.
Have a read yourself and see if you find it illuminating, I certainly did!