As per title, packs 4 x 400g Cans of Napolina Chopped or Plum Tomatoes are £1.94 at Tesco. Now both online and in store. It is claimed to be half price, but that's only because they hiked the price right up recently. Anyway, it's cheaper than buying Tesco own brand (not Tesco Value) and I think these are the best affordable tinned tomatoes you can buy.
Incidentally, for fans of Italian cooking, Somerfield have Filippo Berio Extra Virgin Olive Oil 500ml bottles for £3.85 and BOGOF right now.