The Christmas 2007 event, which allowed players to foster various orphans, improve their conditions, and return them to the orphanage in exchange for items. That's pretty cute in itself, but the CMOH came when some players decided to unofficially adopt their orphans by simply not returning them. And then, after Christmas was over and the children removed from their avatars, demand them back.
Said demands were eventually answered. A Chance Item for February 2008 was adoption forms so the users could get a random orphan for real.