"Turn your laptop into something that any opportunist thief would not look twice at" is the pitch for the "Undercover" laptop sleeve.

As long as said potential laptop thief was not around when Apple was pushing out its manilla envelope MacBook Air promo vids, this clever case will not draw any attention from nefarious types.

Although disguised as a "tatty old envelope", the sleeve is in fact "state of the art", both waterproof and tearproof whilst also providing protective padding.

In two sizes, to fit 8-inch to 13-inch and 13-inch to 17-inch portable PCs, it's on sale now from Lazybone in the UK for £19.99.