http://saturn.jpl.nasa.gov/multimedia/images/image-details.cfm?imageID=1762
What I found interesting is that this photo was a "live shot". The stretched walls of the smaller crater transitioning into the edge of the larger one must actually exist.
It's amazing, really. If you follow the "moons are collections from rings" theory as I do, this is a living example of a moon 1/2 way through the debris collection phase.
I keep looking at that edge and it keeps looking like a fracture surface. They've found "dumbbell" asteroids (Toutatis) -- could Hyperion be a dumbbell asteroid that got hit hard enough to break it into two pieces? Maybe one of the other pieces is one of the smaller moons, or maybe the impact knocked the smaller piece out of Saturn's orbit?
There are going to be some seriously weird theories for this moon, I'm sure.
Images of Toutatis: