Mine vary as interests come and go... for a while, it was a lot of athletic stuff: mountain biking, trail running, powerlifting, brazilian jiu-jitsu, etc. Lately it's been more hardware hacking... (re)learning some basic electronics stuff and hanging out at Splatspace and building stuff.
which is just an opportunity for me to build something that I'll use for electronics experimenting, while getting my hands dirty and using the band saw, drill press, dremel tool, etc.
Guitar. Learning new music and playing old favorites require effort and concentration but it seems like it uses a completely different part of my brain then coding or writing. I can pick up my guitar mentally exhausted then lose myself playing for an hour or two and come out completely refreshed.
Currently it is fitness related. Weightlifting and I want to get into Muay Thai as well. Come the spring, I would like to take a blacksmithing class but we'll see. Nothing outside of computer science/programming really holds my interest for very long.
One of my projects is this thing:
https://plus.google.com/photos/114301088526097505896/albums/...
which is just an opportunity for me to build something that I'll use for electronics experimenting, while getting my hands dirty and using the band saw, drill press, dremel tool, etc.
And then there's this stuff:
https://plus.google.com/photos/114301088526097505896/albums/...
https://plus.google.com/photos/114301088526097505896/albums/...