I didn't know Zuckerberg did a challenge a year. I really like the idea. Focusing on broadening perspectives is pretty neat.
His past challenges are pretty neat, purely on the level of frequency.
- Learning to speak Mandarin - Meeting one new person who doesn't work at Facebook everyday - Writing a thank you note each day to someone who made the world better - Being a vegetarian (or only eating meat if I killed the animal myself) - Wearing a tie every day