Nothing besides an incase sleeve for when it's in a bag.
I take it to school every day in a Tom Binh Brain Bag. It gets used in class, all over the home (couch, bed, desk, shower), in coffee shops, in bars, and in restaurants. There isn't a single scratch on it. I'd be more afraid of it overheating or scratching from putting a case on.
You use your rMBP in the shower?!![]()
I got satin Speck case. It is a bit "softer" than normal see thru case and no, it doesn't scratch the case.