I am a huge fan of Wikipedia. It has loads of information that is generally quite accurate. Posts by people that are funny or untrue are usually deleted rapidly. There was concern in the past that students in school were simply going to Wikipedia for sources and information for term papers, and most teachers and professors were banning this habit.
However, it appears that there may be a role for Wikipedia in the setting of the academic world. A professor at the University of British Columbia is actually encouraging his students to try to get Wikipedia entries acknowledges as a "featured article".