Last year, scientists used a small, remote-control submarine with a bunch of cameras on it to get close-up footage of great white sharks off the coast of Mexico. And I'm sure they collected all kinds of useful data.
But for OUR purposes, the video is cool because a great white ended up ATTACKING the sub, which was basically the same shape as a human leg. So the video is essentially what it would look like if a shark started chowing down on YOUR leg.
(Search for "Slate.com Attacked by a Great White." It attacks it at 1:29.)