Hobby helps your work. Chess is the best hobby

Go is too long.
Poker is a bit boring, and everyone can obtain the skill.
Backgammon, bridge, guitar is not as interesting.
Starcraft, warcraft not as interesting.

Chess has the best balance.

You need a good hobby so you will have something to look forward to during difficult work, read The Now Habit by Neil Fiore.

You also need a hobby to forget about troubling things.