The annual, unofficial "Goth day at Disneyland". Once a year, and organised by some notable figures in the Southern California goth scene, large numbers of black clad freaks descend on the popular family attraction. A number of organised "meets" happen at various times of the day; the last, normally at 8pm, is in the garden in front of the Haunted Mansion, and is followed by a giant group photograph session, and then everybody rides the Haunted Mansion. Between and after those times, you can follow others or make your own way around the park.
In 2001, over 300 Goths of all stripes showed up. It weirds out lots of the tourists, but I think it is an educational day for them too.