What other hobby...

Ceramics is pretty close to infinite. Humans have been making pottery for 50,000+ years and have barely scratched the surface. We have only begun to understand what happens inside the kiln in the past decades. The atmospherics are mind bending. And that is but one small arena within ceramics. Glazes, clay-body glaze interface, clay bodies, forming and shaping. On an on. 

@twoleftears We have a saying at our local camera Meetup Group (which is inactive now) - If it's Black and White, it's art!

I started to say, "sex", but- with all the new, designer diseases out there, it’s now more of a spectator sport.       SO, yeah- porn and Harleys, +1 each.       Then again; I have known people that made collecting diseases SEEM like their hobby!       Kinda went with the Harleys.

Cooking and
Fountain pens (you know, the things some folks call "ink pens" )

I think I'm gonna start selling sildenafil on this web site.