People who play the ridiculous, immature game called Farmville, which is popular on Facebook. These people will often tease you for liking your game of choice if it's not Farmville (such as something more entertaining and hardcore, like World of Warcraft).

Briefly, "the realization that each random passerby is living a life as vivid and complex as your own." Originally from the Dictionary of Obscure Sorrows, which has a lot more beautiful neologism definitions like this you might enjoy.