John Quincy Adams wore the same hat every day for 10 years.
Also John Quincy Adams kept a live alligator as a present from Lafayette, which he kept in a bathtub in the East Wing of the White House.
Bonus fact: John Quincy Adams would frequently go to the library very early in the morning (around 4) but he would have to go through the guest rooms to get there, so guests often woke up scared by the president quietly sneaking through their rooms in the middle of the night. This grew to be such a problem that a /whole new hallway/ was built just for John Quincy to get to the library and is still there to this day. Thanks Egg President!