Some of my favorite memories from MMOs come from participating in -- and even creating -- special events. Level one gnome runs across the world of Azeroth used to be a popular pastime in WoW, City of Heroes is well-known for its constant costume design contests, and not a day goes by without some sort of concert peppering the towns of LotRO.
So what are your favorite player-run events? How have you seen the ingenuity of your fellow gamers blossom into memorable experiences? Did you ever run one yourself? Wake up, splash your face with scalding-hot coffee, and dish!