Reader cashius22 spotted this and I can't resist. It's Lego, and it's Indiana Jones and therefore, it is on-topic.
And it's quite possible that this is viral marketing for the upcoming title (out in June), if not the movie (this week). They roll this sucker in San Francisco, and LucasArts is around the block in the Presidio. Five million Legos is not something you buy or assemble that quick — if it is a solid 5 mil Legos. I don't really see them flaking off as it tumbles, so it may be a bunch of big pieces- parts made by Lego and assembled by this team. Also, it's S.F. in the middle of the day, no moving cars in the shot, very few parked, so they probably got a filming permit. And the big flatbed truck too ... good bet this is marketing.
But it's clever, and I admire any creative impulse that gets you to roll a Lego boulder down a big hill into a parked van. Plus it has a guy dressed as Sallah, and fezzes are awesome. But if this was Boston, they'd all be arrested for terrorism.
LEGO Boulder [YouTube, thanks cashius22]