Just saw this: "What Motivates Wikipedians": review of a survey
<snip> * Altruism and humanitarian concerns * Responding to requests by friends or attempting to engage in an activity viewed favorably by important others * Chances to learn new things * Preparing for a new career or signaling knowledge to potential employers * Addressing personal problems, such as guilt at being more fortunate than others * Ego needs and public exhibition of knowledge * Ideological concerns, such as belief that information should be free * Fun <snip> http://feeds.feedburner.com/~r/oreilly/radar/atom/~3/177322097/what_motivates.html