I have semi-recently come across an incredibly enjoyable board game called "Go" in English ("Weiqi" in Chinese, "Igo" in Japanese, and "Baduk" in Korean).
I've read several posts about other INTPs getting bored and not knowing what to do with themselves. Knowing exactly what those people have been going through, I wanted to offer up this game as a suggestion to occupy time and challenge oneself.
It's a game that is extremely simple in concept, yet extremely difficult in execution (when played against players of similar abilities).
I hope that in learning more about the game, more people come to love it as I have.
I'd love to hear anybody's thoughts!