I really have cut back in recent years. Before pipes sort of subsumed me I collected signed 1st editions of favorite Sc-Fi and fantasy writers, like Ellison, Asimov, Farmer, Heinlein, Bradbury, Le Guin, etc, etc
I also collected some fairly rare Art and architecture books, like a 1st edition of The Metropolis Of Tomorrow by Hugh Ferriss, and Facing East, among other interesting items.
I also collected Arts and Crafts metalware and furniture.
Cooking was a hobby until I got too busy to put much time into it.
Walking, hiking, sneaking into forbidden areas, reading Mysteries, Histories, crap.
Before I was 11 I had read, in translation of course, Aristotle, Plato, Herodotus, Lao Tsu, Machiavelli, Vasari, all of Dostoyevsky, most of Pushkin, Gogol, some Sartre, etc, you know, light weight stuff. When I hit puberty I dumped all that crap and went for comic books and later, girls.
I did some inept writing, played the piano - occasionally for money, practiced photography and was a stringer for the Los Angeles Arts Council, etc. I guess some of this doesn't count since I did get paid for it.
I do art for a living, so it doesn't really qualify as a hobby.
Classic films, a fair amount of silent films. Everyone knows that sound is a fad.
Politics isn't a hobby, it's a blood sport. And almost entirely bullshit.
Otherwise, not much