Everything Sparkyfire writes is correct but it's important to differentiate between a manufacturer's warranty and the retailer's responsibilities under trading standards legislation.
Irrespective of whether a manufacturer offers a lifetime warranty or no warranty at all, it is the retailer who is responsible for ensuring that the products he sells are 'of suitable quality'. If the products do not meet this standard, then the retailer (and not the manufacturer) is responsible for putting matters right. In effect, all manufacturer's warranties (except, possibly, lifetime warranties) are totally pointless. European legislation makes it clear that you can make a claim against a retailer who supplies defective electrical equipment for a minimum period of 2 years (and possibly much longer) after purchase. In many cases a claim for 'consequential loss' may also have validity. Yes, a court may rule that someone should have backed-up their data and therefore reduce the amount of any damages payable but this does not mean that no damages at all will be paid. (If the failure of a hard drive meant that someone lost several days business while they waited for a retailer to put matters right they would most definitely have a valid claim for consequential loss).
Manufacturers are entitled to put a disclaimer in their warranty, excluding liability for consequential losses, because there is no obligation upon them to offer any warranty at all.
Retailers, however, are obliged by law to make reasonable recompense for the failure of their products. Any attempt to get out of their obligations (e.g. by displaying a notice stating "We will not be responsible for . . .") constitutes a criminal offence under the Unfair Contracts Act.
Chris