This is Anthony Pitch's time of the year. He's a Washington, D.C., writer and tour guide who, in the weeks before the mid-January Presidents' Day holiday, brings out an updated little paperback book that's a hit with tourists.
It's called "Exclusively Presidential Trivia," and contains more than 650 brain-teasing questions and answers about U.S. chief executives.
Pitch has also written scholarly books on subjects such as the assassination of President Abraham Lincoln and the burning of Washington by British troops in 1814. But the trivia book is pure fun.
Pitch tosses out obscure facts that, he says, stimulate the memory and provoke an interest in history. Breezy tidbits such as these:
How far was Lee Harvey Oswald from President Kennedy when he shot the president in 1963 in Dallas - assuming you believe he did shoot Kennedy? Answer: 81 meters.
Which fairly unmannered president was visiting the Taj Mahal in India and shouted loudly to see if he could hear his echo? Answer: Lyndon Johnson.
Did you know that Jimmy Carter worked in the White House as a chef in Franklin Roosevelt's administration? It's true - but it wasn't the Jimmy Carter who became president.
Here's one you can take a guess at: How many American state capitals are named after presidents? A colleague of ours guessed 40.
But perhaps surprisingly, it's only four: Jefferson City, Missouri; Lincoln, Nebraska; Madison, Wisconsin; and Jackson, Mississippi. There's a Clinton, Iowa, too, but it's not the capital.
Here's one last one: If both the president and vice president should die in office, who's next in line? It's the speaker of the House of Representatives. Even for many Americans, just the name of the speaker of the House would be trivia. It's John Boehner.
Oh, and Bill Clinton, Jimmy Carter, the two President Bushes, and President Obama are not on any postage stamps. Until this year, the Postal Service had a strict rule that no living person, not even a president, could appear on a stamp.