Dell Home, via its Member Purchase Program, offers its Alienware 17" Vindicator Backpack, model no. AWVBP17, for $66.49 with free shipping. That's tied with our mention from a week ago as the lowest total price we've seen. (It's the best deal now by $14.) It fits laptops up to 17" and is made of high-density nylon. It features three main compartments, a weather-resistant non-slip base, and non-slip padded shoulder and chest straps.
Note: Dell's MPP is available to select groups, including students, government employees, military (active and retired), credit union members, and health care workers.