If you have some mathematical inclination and a couple of hours to spare, you may like watching his (1-hour) Christmas lecture from 2017: https://www.youtube.com/watch?v=BxQw4CdxLr8 — you may need to listen carefully (he's over 80 after all), but some of his humour comes through at moments.
It's a _really_ long interview, +7 hours. But it's also superb. He is interviewed by his friend and colleague Edward Feigenbaum who does a stellar job. He brings out the human Donald Knuth in a remarkable way.
It gave me great respect and admiration for Donald Knuth life and achievements. For me I dare to say it was transformative in regards to human pursuit of knowledge, passion and what it means to be a intellectual human being.
td;dr: Watched a Donald Knuth interview and got a nerd crush
Given this, I pictured a somewhat solitary gentleman - a slightly more dignified version of a modern nerdy basement dweller, disconnected from modern life and humour.
Therefore I find great joy in seeing the words "Bank of San Seriffe". I giggled quite a lot at this. :)
Ps. This description is probably entirely wrong. It's just how I always pictured him as a result of reading that article.