ntl in most cases will not yet have re-couped the cost of the original boxes yet from the subscribers.

I don't really think that you could charge extra for this function, as I doubt many people would take it up. However if it were part of an all round superior STB (like the functions of the Sky+ box for example) then it might have a valid business case, but I doubt their market is big enough to warrant it. Bear in mind the take-up of Sky+ has been quite low, but it is a chicken and egg situation. They're expensive boxes so they cost a lot to buy, but becuase they cost a lot to buy not many people buy them - so they price never drops.

Does anyone know what the length of time the boxes are amortised over? I would presume it to be something like 3 years.

Seriously - thats what I thought the point of a 12 month contract was - to recoup the box costs.

Even more so when they can refurb / recycle boxes.

Maybe if they switched to a system whereby the user could purchase the box for (say) £300..