The most celebrated novel of the 20th century, Ulysses, and its author, James Joyce, are celebrated each June 16 on what's called "Bloomsday."
The "Bloom" part comes from the central character in Ulysses, who was named Leopold Bloom, and the date from the day in which the novel's 24-hour narration takes place, June 16, 1904.
Bloomsday is celebrated widely in Dublin, setting of the novel, and truly in spots around the world wherever there are fans of Joyce and his writings.
The Dublin festivities include pub crawls, which tend to incline me toward celebrating the occasion in that Irish city.
Maybe I can make it there in 2011.