Facebook co-founder/ alleged rip-off artist/ movie villain/ movie hero Mark Zuckerberg went on a walk with his girlfriend Priscilla Chan in Palo Alto yesterday like he didn't have a care in the world.
Meanwhile, the movie about his life -- "The Social Network" -- was #1 again at the box office ... despite the fact that Mark's people insist it's pure "fiction."
You know what's cooler than this photo? A billion dollars.
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