Look at the Arcteryx Blade. It is pricey but comes in three sizes and is built like a brick dookiehouse. http://www.arcteryx.com/Product.aspx?Mens/Packs/Blade-15
I'm in the market for the same thing but for a 13" MBP, currently I'm looking at the timbuk2 Q, the booq mamba pack, and the crumpler king single. Has anyone had any experience with any of these?
avoid the booq mamba range, the construction quality is extremely poor and the material rips in just about every place. ive still got to replace mine under warranty.