This 27 litre rucksack is reduced from £60 to £17.99 delivered. It can take a 17" laptop, has good quality shoulder straps with a sternum strap, and is covered by a 30 year warranty. This is not a current colour. Other colours are available at significantly higher prices. Looks like a good item at this price.
Eastpak Unisex Hudson Backpack (Dusk Lines) - 70% discount £17.99 @ amazon