World of Warcraft, Dungeons and Dragons Online, EverQuest II, Guild Wars, Lord of the Rings Online, Events (Real-World), Events (In-Game), Opinion, Star Wars Galaxies, RuneScape, Guild Wars 2, Humor, Perfect Ten, Miscellaneous, Neverwinter
I think a good goof has to have several qualities to make it truly memorable. It needs to be original. It needs to be actually amusing, whether or not you "fell for it." And it needs to tweak our expectations and understanding of how MMOs work. Sometimes there are even important ideas that emerge from these jokes that could, indeed, make these titles better.
So let's go through my favorite MMO April Fools pranks of all time, as catalogued by yours truly!