eXpansys still offers the Airbak Professional 15.4″ Notebook Backpack, model no. PR318, for $23.99 with free shipping. That’s tied with last week’s mention and the lowest total price we could find by $2. It features an inflatable 15.4″ laptop compartment that provides up to 100 lbs. of impact resistance, multiple interior pockets, MP3 player pocket, and more.