Well, that's why most (not all) of us use some sort of case.
Wax the crap out of it. Seriously. Use an abrasive compound wax then wipe it off. Then use a carnuba based polishing wax and wipe off. Keep doing this until most (if not all) scratches are eliminated. Then, goto amazon.com or your local best buy and buy a zagg shield ( or body guards) and use just the back part to protect it from more scratches.