LADY JANE GREY is called the "nine days queen" thanks to her short reign in 1553. In those days royal succession depended as much on political intrigue as on bloodlines. On the throne was a sickly boy king, Edward VI, the son of Henry VIII and his third wife Jane Seymour. Edward's lord chamberlain, John Dudley, arranged a marriage between his own son and one of Edward's cousins, the 15-year-old Jane Grey. Dudley's idea was to keep the throne "all in the family" should King Edward die. Things nearly worked out the way he planned: Edward did die on 6 July 1553, and Dudley's supporters declared Jane Grey to be the new queen.

However, Edward's half-sister Mary Tudor had other ideas. The daughter of Henry VIII's first wife, Catherine of Aragon, Mary had a stronger claim to the throne and the muscle to back it up. After nine days Jane Grey was forced to step down and the new Queen Mary tossed her in prison. Jane spent her 16th birthday in the Tower of London, and the next year she and her young husband were beheaded.

U.S. President WILLIAM HENRY HARRISON was 68 years old when he delivered a longwinded inaugural oration of 100 minutes in freezing Washington weather on 3 March 1841. Harrison refused to wear a coat or hat, and the next day he came down with a cold (as did, no doubt, many of his listeners). Harrison's cold turned into aggressive pneumonia and he died on April 4th, having been president for a mere 32 days.

An eerie sidelight: Harrison's death allegedly was predicted in 1836 by Tenskwatawa, the brother of Indian chief Tecumseh. Harrison became the first in a series of presidents elected at 20-year intervals who died in office -- the so-called Curse of Tecumseh.

Pope JOHN PAUL I outlasted Harrison by one day, serving for 33 days in 1978. The former Albino Luciani was a surprise choice for the papacy, having had a relatively low-profile career as pastor, teacher, and Patriarch of Venice. Even more surprising was his demise: an attendant found him dead in bed a little more than a month after his elevation to Supreme Pontiff. The cause of death was given as a heart attack.

The Pope's sudden death was a boon for conspiracy theorists suspicious of the Vatican's fabled wealth and secrecy. (The church didn't help matters by refusing to allow the Pope's body to be examined by Italian authorities.) The general allegation was that John Paul had been murdered by Vatican insiders who didn't want an "outsider" Pope rocking the boat. No real proof of this has ever been offered, though a 1984 book on the topic, In God's Name, was a best-seller.

U.S. Senator DAVID RICE ATCHISON may have had the shortest term of all: supporters say he was the president of the United States for one day in 1849. On March 4th of that year Zachary Taylor was due to replace James Polk as president, but Taylor refused to take the oath of office on a Sunday and delayed the swearing-in until the next day. The argument goes that neither Taylor nor Polk was in office from noon on March 4th until noon on the 5th, making the president pro tempore of the Senate -- Atchison -- the acting U.S. president for 24 hours. In point of fact, Atchison was never sworn in or otherwise designated as Chief Executive. (He was later quoted as saying that he spent most of the day sleeping.) That hasn't kept trivia buffs from promoting him as the neglected "12th president." According to the U.S. Senate's own history of the event, "For the rest of his life, Atchison enjoyed polishing this story, describing his 'presidency' as 'the honestest administration this country ever had.'"