This is allegedly a 5 million piece LEGO boulder being rolled down a hill in San Francisco. I find it hard to believe it's solid and 5 million pieces because it seems pretty light. But who knows, stranger things have happened (my penis once fell off in the shower after I scrubbed it with a loofah). So these guys roll this big-ass LEGO boulder down a hill while some guy dressed loosely as Indiana Jones runs in front of it (and another in a fez that may or may not be Sallah makes bad commentary). Eventually the boulder bounces off a tree and stops after hitting a parked van. Now we could bicker back and forth all day long whether or not this is fake, so for the sake of argument we'll just agree that it should have been a lot cooler.
UPDATE: Turns out the boulder is styrofoam in the middle. FAIL. Thanks Detective Steph.
Thanks to Altaire, who could train horses to make more realistic LEGO boulders