I am completely and utterly obsessed with this video. It's actually an advertisement for the Sony Bravia TV from 2005 [Edit: I had originally said this was from 2010, but was kindly corrected by a number of astute readers], however I never saw it, so it's new to me (and hopefully some of you).
Here's the premise: 170,00 bouncy balls are bounced down a hill in San Francisco, creating a cascade of colorful chaos. It's truly a beautiful site to behold (slow motion helps). And for all you skeptics out there that are thinking it's just CGI: take a look at the video at the end of this post that shows how this super ball stunt was done.
And this video shows the making of the bouncy ball commercial:
Now if you'll excuse me, I think I'm going to go buy some bouncy balls and drive my co-workers insane.