Defferential "How It Works"

Here is a really cool video on how a differential works. Sometimes, you put parts in your car or bike, not really knowing how they operate, just that it all "makes it go". This is a real simple idea, engineered perfectly! Everytime I watch a clip like this, I always wish I was as smart as some of the engineers that came up with this stuff. Video borrowed from the Jalopy Journal, via YouTube.