Most often, I read books (mostly epic-fantasy and other fiction sub-genres). For details checkout by Goodreads profile.
Frequently I go for long walks, usually early morning or late night. My locality happens to have a lot of greenery and a large national park nearby despite being located in one of the most posh locations of the city.
Occasionally, I read (and also draw) manga.
Occasionally, I play games (mostly racing and role-playing). No where close to competitive levels.
I spend quite a bit of time on Stackoverflow, Hashnode etc.
I frequently explore technical topics which are not even remotely close to my primary job - I have a tendency to get absorbed for several hours to days in things that have no direct relationship to what I need to do and no apparent benefit to my primary role. It is fun but more often than not, does not add any real value to my work-profile.