I also really like memorizing labels!
With special interests for me it's Fiction Podcasts, B.O.B. TTRPGs, Good Omens in all it's forms (the book is my favorite though), art in general and things that blend genres specifically? I know thats kinda vague but it is a topic I can talk about for ages and am low-key obsessed with and last but not least: Homestuck. I'm serious that webcomic permanently lives in my brain.
My last hyperfixation which was FRUiTS magazine and generally a lot of fashion and fashion history related stuff is kinda in the process of dying down so I think right now I don't have a current hyperfixation