I'm a new ham radio tech, I don't even have a radio yet, but I still count it as a hobby!
I like studying languages/linguistics in general, and I'm studying Japanese in particular. I'm considering French too, after I get a good grasp on Japanese (years from now, that is). I like science, math, and especially history, but I'm not sure those are really hobbies. I have watched some anime and read some manga, but that's not really a hobby for me either. Mostly I spend my time studying, writing, and playing games.
Edit
ココロさんの絵が好きですよ!上手です