Another quick and simple recommendation, the Belkin Merge Sleeve for 7″ Tablets
If, like me you’re not into keeping your tablet in one of those Swiss Army style cases that can turn into stands or keyboards with a few simple twists, but prefer a simple bumper case, and yet would like some extra protection from scratches and the like when you bung your tablet into a rucksack, then you can’t go wrong with this.
Got mine locally for €20 but if you look around online you may well find the Belkin Merge Sleeve for 7 inch tablet at a better price.