My laptop is in a fortress,
I have a thin piece of foam I slide between keyboard and screen to prevent scratching,
Then its in an Incase 13" Macbook sleeve
Then I put it inside the 15" tougher case that comes with the larger Crumpler laptop bags
Then i slide all that inside the protected laptop compartment of my Crumpler bag.
All that protection does get a tad heavy but its fine and worth it as i no longer have apple cover for the laptop.
The crumpler bag i have is a Dark green and Orange Cheesy Disco.
This bag has lots of pockets and tones of space, when it is full its quite hard to get something out though.
p.s. my laptop is a 13" White Macbook