This website features presidential advertising campaigns going all the way back to 1952. I just generally love the history of the US presidency and the presidents themselves, it's a fascinating office that has been filled by some fascinating men. My mom (shout out to kimshibsss) and I are currently on a mission to visit every presidential library in the US (7 down, a bunch to go!)
When I was interning at Amazon in fall 2017 I constructed a shrine on my desk. (Note from 2022 Trevor: This seems hilariously dated now but keeping it around as a fun relic of what 2017 me was like)