Show HN: Building a 42-inch E-Ink frame for generative art 3 years ago
I love it. 2 Ideas:
You should upload a massively complicated where's waldo like scene and have waldo appear in different places each hour.
Have a portrait with lots of subtle details but they change slowly over time. Ex. girl goes from earing-less to small earings to big earings. Just have lots of small details subtly change but at a rate which makes them hard to detect.