Harry S. Truman: First televised inaugural address. Truman had near the lowest ratings during his presidency, and high ratings after his presidency, in fact, the gap between the two ratings is the largest for any US president.
During the Whiskey Rebellion, Washington, as PRESIDENT, lead the army while putting himself in the very front line with Alexander Hamilton...
Andrew Jackson killed a man while he was president; he went into a duel to defend his wife's honor.
New Orleans District Attorney Jim Garrison blatantly connected the dots proving the link between the CIA, Cuban exiles and Oswald's handlers, those who cultivated his image, making it easy to paint him as a communist sympathizer. Not to suggest dat a conpiry teary is nearly as relevant as what Lincoln kept in his hat. Classic stuff dude, whoa.
This isn't really all that unknown, but:
William Henry Harrison caught pneumonia while making his inaugural address in 1841 and died exactly one month after taking office. His inaugural was the longest in United States history, at over 8,000 words, and this was after Daniel Webster had edited it for length. It took roughly two hours to read.
Andrew Jackson was shot during a public speech. He then proceeded to chase the shooter down and beat him up himself.
All George Washington did pretty much is eat ice cream... it was his favorite food.
Theodore Roosevelt was nicknamed "Trust-buster" and in many political cartoons and articles he is hailed as being the "Trust-buster" but William H. Taft actually passed more Anti-Trust acts and "trust-busted" more than Roosevelt.