Tabletop rpgs such a D&D 5e, Call of Cthulhu, Cyberpunk 2020, Tails of Equestria, and a whole lot more. Have GM/DMed a lot, but only been a player a few times.
Computers and algorithmic design. Making both little programs that do simple tasks, as well as large applications to handle large inputs. Always eager to try and apply my knowledge, or learn something new along the way.
Writing a variety of things. Mainly fiction, though research is interesting if I have the time. Working on setting up a FimFiction account once I have more free time. I'm trying to pursue a side gig with a Patreon writing page.
Trying to figure out how to art so I don't have to commission as much.
Nit picking apart headcanons and unnecessarily detailed fictional worlds. This ties into the above tabletop GM role. I like to plan out the systems a world has, and so like to figure out continuity and other details.