A lot of good suggestions. I personally do as much physical stuff as possible because as programmer I get no workout. But recently I have picked up a new hobby

A lot of good suggestions. I personally do as much physical stuff as possible because as programmer I get no workout. But recently I have picked up a new hobby that I would say is fitness for brain. It is listening to music with mindfulness. Not as a critic. When listening music, I actively pay attention to each note and word. This usually lead me into trance sort of state. It might be ASMR, Frisson, or a meditative trance. The thing is after actively listening to music, I feel relaxed and energized. I know our community is big on meditation but I could never sit still long enough when meditating on breath. Listening to music may not be same but I feel like it gives me a lot of benefits that people claim about meditation. Another thing is you can listen to music anywhere. I listen to music 1. in backyard while drinking beer, 2. in family room, while everyone is doing their thing, 3. in plane, of course 4. bathing in tub (without headphones though). Lastly, the music I listen to is sort of chill like Lana Del Ray.