It's not bulletproof, but TUMI's Southington Backpack does have a carbon fiber construction and ID Lock features strong enough to protect your tech and gear from the dangers of the daily commute.
The TUMI CFX collection is set off by its American-made carbon fiber CX6. The material undergoes a wet infusion process during manufacturing that TUMI says results in a superior textile that's high-strength, low-stretch, lightweight, and soft enough slung across your back that you won't feel like you're going to school or work dressed as a Teenage Mutant Ninja Turtle.
In addition to its carbon fiber shell and leather trim, the Southington bag is built with TUMI's ID Lock, a layer of protection for the personal data encoded on most of your IDs, credit cards, and passports.
Of course, given what the TUMI CFX Southington costs, if I were a thief I might rather swipe the whole backpack than try skimming off the information inside it.