Entomology.
I may spend a month or so with an extremely intense interest into a particular field before I'll move on to a different interest which sometimes is completely unrelated. Currently, I am studying bugs.
My most recent series of intense interests which I can remember have been Flat-Earth theory, rats and rodents, ancient hebrew and modern yiddish, and dietary sciences. Once I feel I am sufficiently infused with enough information about a particular subject I typically move on.
Aspie trait, or just personality quirk?