Ebay offers Targus Octave II Laptop Backpack for $12 (reg $40) with free shipping.

Product Description:
The Targus 1516Octave II Backpack is a functional and lightweight pack with easy access pockets to stylishly carry the days essentials. It will protect your tech in its dedicated padded laptop pocket, while organizing your gear in its built-in workstation. Two front pockets make it easy to stash your on-the-go items like your phone, wallet, or charger, and you can keep your water or drinks handy in its two side water bottle pockets.
Features:

• Paddled laptop pocket to accommodate 15.6" laptop or smaller
• To safeguard and keep your laptop safe.
• Secondary compartment
• Provides built in work-station.
• Padded should straps and back panel
• Offers comfort while carrying.
• Easy access cable pass-through port
• Makes working on-the-go convenient.
• Additional compartments
• Two mesh water bottle holders and two front stash pockets.
• Reflective accents for increased visibility
• Allows for everyday use.
• Comfortable carry handle
• Easy to pick up and go.
• Warranty
• Limited Lifetime.