The Slow Mo Guys pointed their Phantom at a Canon DSLR to demonstrate how a single lens reflex camera works. At 10,000 frames per second, you can see the the mirror and rolling shutter mechanism in action in several demos.
In addition to showing different shutter speeds, they examine the rolling shutter phenomenon. If you look at the shadow of the cork hitting the subject’s face in the still frame below, it appears to be furhter along in its trajectory.
As I discussed previously, a rolling shutter can cause interesting artifacts in photos and video: