Supply and demand
I've heard that [certain] UK distributors have marked up existing [pre-flood] large capacity SATA stock by as much as 40% to cover their anticipated shortfalls.
First hand I've noted a marked shortage of external hard disks at my local Tesco [other supermarkets are available] who's shelf is usually adorned with a mixed bag of 250GB - 2TB USB external disks. I've never seen a tech shelf in any supermarket empty out so quick. All that's left now are a few obscure 2½ capacity disks (250 & 320GB) and one overpriced Seagate Options 2½ external 1TB disk going for the bargain price of £97! A whopping £30+ more than I paid for mine four months ago.
Are the tech savvy users stocking up before we feel the real impact of this shortage, or is "Mr Average" a little wiser and buying while stocks last? Who knows, but something is motivating people to buy this kind of kit from the super stores.
Either way, someone's going to cash in on this and the clear losers are the consumer as we'll be paying more for our Laptops, PCs and DV Recorders as the demand exceeds the supply, thus escalating the price.