Wackypedia.
Wikipedia is apparently going to tighten up access to modifying its content, freezing certain sections of their entries as permanent, so that they can't be defaced.
The amusing bit, however, is that they referenced a recent example of vandalism, where following the election of the new Pope Benedict in April, a user substituted the pontiff's photo on the Wikipedia site with that of the emperor from Star Wars.

Sure, there were parodies going around, but I think the fact that someone actually did this is pretty amusing...