I have seeded my list with the following fun and unexpected applications, but I would appreciate more pointers:
* Applications of ML in art, e.g. DALL-E, DeepDream, OpenAI's MuseNet and JukeBox.
* Computational origami, highlighting some of the work of Erik Demaine.
* A couple of examples of how some ideas from CS can be applied to day-to-day life, inspired by "Algorithms to Live By" by Christian and Griffiths, e.g. looking at the exploit vs explore trade-off when selecting a restaurant in town.
* Knuth's papers on The Complexity of Songs, and The Toilet Paper Problem.
* A couple examples of esoteric languages.