Moving away from the algorithm: I've been enjoying letterboxd a lot lately, and thinking about how rich the world of available films looks jumping across lists, directors, and especially people's favorites. Compared to the home pages of Netflix or Prime it feels much richer, less flat. Even before where I'd try and go through something like classics or 'highly rated' sections of Netflix it felt like being stuck in a rut.
Similarly I've been enjoying my Spotify custom app where I add albums and then it shows me a random set of six to play from. I think it's a good mix of intentionality and serendipity. I'll often go through an online list or remember an artist I want to add and do that through the admin interface. It's not necessarily that I want to listen to that album right now, maybe it's not the right mood, but I like being able to add it to a list where I know I'll see it again some day in the future.